Custom O-Ring Manufacturers and Suppliers for Industrial Applications

Disclosure: Vietnam Silicone Rubber (Minh Fast) publishes this guide and is entry 9 on the shortlist. Supplier details come from each company's public materials. Confirm current terms with any supplier before ordering. 

The right custom O-ring manufacturer is the one that can make your material, hold your tolerances, document its quality and ship to your market. This guide compares nine O-ring manufacturers and suppliers on those points and shows how to specify an order.

What O-rings do and what they are made of

An O-ring is a circular elastomer seal. Compressed in a groove between two surfaces, it blocks liquids or gases from passing. It can seal static joints, such as flanges and covers, or moving parts, such as pistons and rods.

Most O-rings come from a few material families:

• Rubber O-rings: nitrile (NBR), EPDM and fluoroelastomer (FKM) are common choices for oil, water and chemical service.
• Silicone O-rings (VMQ): valued for wide temperature range and food and medical compatibility, mainly in static seals.
• Clear silicone O-rings: translucent silicone grades, used where appearance, visual inspection or cleanliness matters.

Typical uses include hydraulic and pneumatic fittings, pumps and valves, food and beverage equipment, medical devices, coffee machines, water filters and electronic enclosures.

How to read this guide. Statements about a supplier come from that supplier's own public pages and are marked as published. Material and specification advice is general industry guidance, not a claim about any one company. Where a detail was not found, the guide says to confirm it in your RFQ.

How the shortlist was built

Each company needed four things: a public O-ring or custom-seal offer, a stated custom capability, a traceable location, and silicone or rubber coverage. The list is not a ranking. It runs from established global names to Asia-based sources, so buyers can compare different supply models.

Public pages rarely state production capacity, tolerance classes or export terms. Those items are listed as "confirm in RFQ" rather than guessed.

The shortlist at a glance

Top custom O-ring manufacturers and suppliers

1. Parker O-Ring & Engineered Seals Division (USA)

Parker's O-Ring & Engineered Seals Division develops, manufactures and supplies precision O-rings and custom sealing solutions. It is a fit for buyers who want a large engineering organization behind standard and custom rubber O-rings.

• Location and contact: 2360 Palumbo Drive, Lexington, KY 40509, USA. Phone +1 859-269-2351; ordmailbox@parker.com.
• Published capabilities: custom molded shapes, free engineering assistance and seal-design software, with worldwide distribution listed in the Parker O-Ring Handbook. Parker states it has made O-rings since 1944.
• Quality system: Parker states its plants are TS 16949, ISO 9001 and AS 9100 certified. This comes from an older Parker page, so request current certificates.
• Confirm in RFQ: minimum order quantities for custom tooling and lead times to your region.

2. Trelleborg Sealing Solutions (global)

Trelleborg is a global sealing specialist. It states that any size of O-ring, standard or custom, is available alongside custom-molded seal designs and bonded products.

• Location and contact: global network; use the local sales company listed on trelleborg.com.
• Published capabilities: its Skellefteå, Sweden plant makes O-rings and bonded seals and lists FKM, EPDM, NBR, HNBR, silicone (VMQ) and CR among its materials. The plant states it works to ISO/TS 16949 and ISO 14001.
• Best for: buyers who need unusual diameters, bonded seals or several elastomers from one source.
• Confirm in RFQ: which plant will make your part and whether it holds the same certifications as the Skellefteå plant.

3. Freudenberg Sealing Technologies (Germany, global)

Freudenberg's Dichtomatik brand states that custom-molded parts can be made from a reference sample, a drawing or a specially created design, from pilot-mold hand samples to extremely small runs and series production. Freudenberg is one of the larger sealing groups, so it suits OEM programs.

• Location and contact: Höhnerweg 2-4, 69469 Weinheim, Germany. In North America, Freudenberg-NOK Sealing Technologies operates from Plymouth, Michigan.
• Published capabilities: Freudenberg's own magazine says it has more than a thousand elastomer compounds. Typical molded-part materials on the Dichtomatik page include NBR, FKM, EPDM, VMQ, FVMQ, HNBR, ACM, SBR, PTFE and TPU.
• Confirm in RFQ: which Freudenberg line (premium or Dichtomatik) would quote your part, since the Dichtomatik page excludes safety-critical uses such as automotive, and any minimum quantities.

4. Apple Rubber Products (USA)

Apple Rubber designs and manufactures O-rings and custom seals in Lancaster, New York. Its published range stands out for micro O-rings, liquid silicone molding and prototyping.

• Location and contact: 310 Erie Street, Lancaster, NY 14086, USA. Phone +1 716-684-6560; info@applerubber.com. The toll-free line, 800-828-7745, is for the US and Canada only.
• Published capabilities: over 1,000 MicrOring sizes from 0.008 to 0.039 inch inside diameter; liquid injection, transfer and compression molding; single-cavity O-ring molds cut the same day for prototypes; a Class 7 cleanroom; silicone offered "translucent to solid".
• Quality system: ISO 9001, AS 9100, RoHS and REACH compliance, and ITAR registration, per its capabilities brochure (dated May 2021). USP Class VI and ISO 10993 certification is listed as available.
• Confirm in RFQ: export terms outside the US and Canada.

5. Marco Rubber & Plastics, now Marco Sealing Solutions (USA)

Marco supplies standard and specialty O-rings, seals and gaskets and was founded in 1980. Third-party company profiles place its headquarters in Seabrook, New Hampshire, and its website lists the phone number +1 603-468-3600.

• Published capabilities: product types include O-rings, gaskets and seals, diaphragms, molded rubber and plastic components and kitted assemblies. Its materials list names FKM, Markez, EPDM, NBR and silicone, and it lists FDA, NSF and USP Class VI compliant compounds. Its website shows an ISO 9001 badge.
• Supply model: Marco's site describes a global sourcing network, and some directories call it a supplier rather than a single factory. Ask which plant will mold your parts.
• Useful resource: it publishes a comparison of silicone and rubber O-rings for application engineers.
• Confirm in RFQ: lead times for custom tooling, certificates by plant and international shipping terms.

6. Canyon Components (USA): clear silicone O-rings

Canyon Components is the clearest match for buyers searching for clear silicone O-rings suppliers. Its online catalog lists translucent silicone (VMQ) O-rings in AS568 and metric sizes, and it also makes custom O-rings.

• Location: 8 Industrial Way, Bldg D, Unit 4, Salem, NH 03079, USA. Phone +1 603-614-5677; sales@canyoncomponents.com. The site shows a BSI ISO 9001 badge.
• Published clear silicone grades: for example SI60TR05 is a translucent, platinum-cured, 60 Shore A silicone listed as USP Class VI, FDA compliant and cleanroom manufactured, with a stated range of -55 to 225 °C. SI70TR05 is a 70 Shore A grade also listed as 3A Sanitary. Lower-hardness general-purpose clear grades are listed too.
• Other published capabilities: oversize O-rings by continuous molding or splice-and-vulcanize, and reverse engineering of existing parts.
• Confirm in RFQ: certificates for the exact compound, lot traceability and export shipping.

7. SPP Industrial Rubber (Thailand)

SPP began in 1974 as Tanasap Rubber in Bangkok and moved its factory to Samut Sakhon Province in 1989. Its O-ring page describes a manufacturer that specializes in custom-sized O-rings. Address: 80/87 Moo 5, Om Noi, Krathum Baen, Samut Sakhon 74130, Thailand; email spp-contact@sppindus.com.

• Published silicone O-ring data: -60 to 220 °C, 20 to 90 Shore A, listed as food-grade with an FDA certificate.
• Published size range: custom inside diameters from 2 mm to 1,000 mm appear on its natural rubber O-ring listing. Confirm the range applies to silicone.
• Other materials: NR, NBR (40 to 90 Shore A), SBR, EPDM, HNBR, neoprene, PU, PTFE and Viton O-rings are also listed.
• Confirm in RFQ: certificate copies, tolerance class and export documentation.

8. Best Seal (Xiamen, China)

Best Seal (Xiamen Best Seal Imp and Exp Co., Ltd) lists custom silicone O-rings, gaskets and seals made from VMQ, and says its factory works to DIN, ASTM and FDA standards. It publishes more commercial terms than most suppliers here, but the page contradicts itself in places.

• Location: Unit 522-525, Gaodian Road 6#, Huli District, Xiamen, China. Phone +86 592-5782315; email yunying2@bestsealhk.com.
• Materials: NBR, EPDM, silicone, FKM and PTFE are listed. Silicone is listed at 20 to 90 Shore A, in black, brown, transparent or custom colors.
• Certifications: the page lists ISO 9001, CE, UL, FDA, NSF, WRAS, RoHS, REACH and SGS. These are self-declared on a product page, and no certificates were reviewed. Published terms: no minimum order (from one piece), 3 days from stock, 10 to 20 days for samples from a new mold, and shipping by express courier, air or sea from Xiamen, with freight on samples paid by the customer.
• Confirm in RFQ: certificate copies, and whether the company manufactures directly or trades: its legal name says import and export, while the page says "our factory". The page also lists the top temperature as both 250 and 230 °C, so ask for a data sheet.

9. Vietnam Silicone Rubber (Minh Fast), Vietnam

Vietnam Silicone Rubber Minh Fast Company Limited makes custom silicone and rubber components under OEM and ODM terms. Its website lists silicone O-rings, V-rings and gaskets among its industrial products. It is a fit for buyers who already have a drawing, sample or defined size and want a Vietnam-based source for silicone O-rings and seals.

• Location and contact: head office at No. 1/19 Luong Khanh Thien Street, Tuong Mai Ward, Hanoi. The order-process and FAQ pages list the factory at Km 33, ĐT 379, Văn Giang, Hưng Yên. Phone, WhatsApp and Zalo: +84 8899 14599. Email: Minhfastsales@gmail.com.
• O-ring product pages: the Round Silicone Gasket – Silicone O-Ring page lists silicone, heat-resistant silicone and food-grade silicone, 30 to 80 Shore A, sizes and thickness to customer requirements, and several colors. It says orders are accepted from samples, drawings or custom dimensions.
• Application-specific O-ring: the Silicone O-Ring for Coffee Machines page (code SI015) lists standard and custom sizes, custom colors and a 15-day lead time.
• Related seals: the V-ring page (code SI081) offers OEM and ODM changes to dimensions, hardness and color.
• Equipment: per its facilities page, a vertical molding machine, an LSR injection molding machine, CNC milling for mold making and rolling machines for weighing, mixing and shaping silicone.
• Services: OEM, ODM and private-label support, from small batches to large orders.
• Quality and materials, as stated by the company: imported silicone from the United States and Germany with CO and CQ certificates; HACCP, ISO 13485 and ISO 9001:2015 certifications listed on its FAQ page; FDA-compliant, BPA-free materials.
• Export: the home page cites experience exporting to the USA.

Not stated on the site: ask in your RFQ

• Clear or translucent silicone O-rings, and O-ring grades in NBR, EPDM or FKM (the V-ring page names NBR, SBR and FKM for V-rings only).
• Tolerance class. The round gasket page cites AS568 and JIS but gives no class.
• Whether your part is molded, spliced or cut to length. The round gasket page describes cut-to-size installation.
• Minimum order quantity, production capacity and shipping terms. The site's delivery policy page was empty.
• Copies and scope of the ISO and HACCP certificates, which appear on the site as images.

Supplier comparison: what each company publishes

Apple Rubber, Canyon Components and Best Seal publish clear or transparent silicone, and only some suppliers publish hardness and temperature data. "Not stated" means the pages reviewed did not say, not that the capability is absent.

Hardness and temperature data published

No supplier reviewed published tolerance classes, production capacity or lead times for custom tooling. Request an ISO 3601 or AS568 tolerance class, a monthly capacity figure and a tooling lead time in every RFQ.

Standard vs custom O-rings: when to go custom

Choose a standard O-ring when your groove follows AS568 or ISO 3601 and a stock compound meets the service conditions. Choose a custom rubber O-ring or silicone O-ring when the size, material or performance falls outside those limits. This section is general industry guidance.

Go custom when:

• The groove or housing is non-standard, or an inch size has been swapped for a close metric size. AS568 and ISO 3601 sizes are not interchangeable, and the wrong squeeze can leak.
• The diameter is very large. Some suppliers make oversize rings by continuous molding or by splicing and vulcanizing a cord.
• The application needs a specific hardness, a color for identification, a clear grade, or food or medical documentation.
• Volume justifies tooling, or one molded seal can replace a multi-part assembly.
• You need private-label packaging or a seal sold under your brand.

How to choose O-ring material and specifications

A supplier can only quote accurately if you define the size, hardness, temperature, pressure, media and type of motion. This section is general industry guidance. Ranges vary by compound, so confirm against the supplier's data sheet.

Dimensions

• Inside diameter (ID), cross-section (CS) and outside diameter (OD): OD = ID + 2 × CS. State which standard the size follows (AS568 or ISO 3601) and the tolerance class you need.
• Squeeze: static seals are commonly designed for about 15 to 30 percent compression of the cross-section. The groove dimensions, not the O-ring alone, set this.

Hardness (Shore A)

Softer compounds seal at low pressure and on rough surfaces but extrude more easily. Harder compounds resist extrusion at higher pressure but seal less readily at low pressure. Around 70 Shore A is a common general-purpose starting point.

Material

Pressure, media and application

• Pressure: higher pressure calls for harder compounds and, above moderate levels, anti-extrusion backup rings.
• Media: check the compound against every fluid it touches, including cleaning agents. Use the supplier's chemical compatibility chart, not general rules.
• Static or dynamic: silicone suits static sealing. Moving seals need abrasion resistance and lubrication, which usually points to other materials.
• Compliance: state the regulations for your market, such as FDA, USP Class VI, 3A Sanitary, RoHS or REACH, so the compound is chosen and documented correctly.

Clear silicone O-rings and silicone vs rubber O-rings

Clear silicone O-rings

Clear silicone O-rings are translucent silicone (VMQ) grades. Canyon Components publishes clear grades from 30 to 70 Shore A. Some are platinum cured and listed as USP Class VI and FDA compliant, and one is also listed as ISO 10993-1 compliant.

Clear grades help when you want to inspect a seal by eye, avoid pigments in food or lab equipment, or keep a clean look in a consumer product. The points below are general guidance.

• Platinum-cured grades are often chosen where cleanliness and low extractables matter.
• Clear grades can differ from standard pigmented silicone in tear strength and compression set. Read the grade's data sheet.
• When you request a quote from clear silicone O-rings suppliers, ask for the compound number, cure system, certificates for the exact grade and batch traceability.

Silicone vs rubber O-rings

Silicone is not the default best choice. Match it to the service:

• Choose a silicone O-ring for wide temperature swings, food or medical contact, UV and ozone exposure, and static seals.
• Choose a rubber O-ring in NBR for oils and fuels, EPDM for water and steam, or FKM for aggressive chemicals and heat, and for most moving seals.
• Ask the supplier to offer both materials for the same groove if you are unsure. A good custom O-ring manufacturer will say when silicone is the wrong answer.

How to request a quote and verify any O-ring supplier

General guidance. A complete RFQ gets a faster and more accurate quote from any custom O-ring manufacturer:

• A drawing, or the ID, cross-section and OD, or an AS568 or ISO 3601 size
• Tolerance class and the standard it follows
• Material and Shore A hardness, or the service conditions if you want a recommendation
• Temperature range, pressure, media and whether the seal is static or dynamic
• Certifications required in the destination market
• Prototype quantity and expected annual volume, plus the delivery date
• Photos or a physical sample if no drawing exists
• NDA terms, if the groove or housing design is proprietary

Before you commit to tooling with any supplier:

1. Ask for certificates with a number and issuing body, not only a logo.
2. Check that the address matches across the company website, maps and trade directories.
3. Request material certificates and a dimensional report on the samples.
4. Approve samples in writing before tooling starts.

Working with Vietnam Silicone Rubber on a custom O-ring

Buyers can start from a drawing, dimensions, photos or a physical sample. The round silicone gasket page says orders are accepted from samples, drawings and custom dimensions. The company's Silicone Production Order Process sets out these steps:

1. Inquiry: send photos or 3D drawings, size, thickness, color, the silicone type, quantity, expected delivery time and any special requirements.
2. Quotation: the company evaluates complexity, selects materials and returns costs, estimated production time and payment terms.
3. Sample: a prototype is made from the approved information and sent to you.
4. Approval: you check dimensions, shape, surface, color and properties such as hardness, then approve or request changes.
5. Mass production: the production mold is made, silicone is injected and vulcanized, and each product is inspected.
6. Delivery: goods are packed and shipped to the agreed address.

The company's contact page says its custom molding suits partners who have finished design work and hold CAD drawings or specifications. If you only have a worn part or a photo, say so in your first message.

Send your custom O-ring requirements

Planning a custom O-ring order from overseas? Send Vietnam Silicone Rubber your drawing, dimensions, photos or sample, plus material, Shore A target, application and quantity. If you need a rubber grade such as NBR, EPDM or FKM, ask whether it can be supplied. In the same message, ask for the tolerance class, minimum order quantity, shipping terms and copies of its certificates.

• WhatsApp, Zalo or phone: +84 8899 14599
• Email: Minhfastsales@gmail.com
• Quotation form: Contact – Get Quota

Frequently asked questions

What does a custom O-ring manufacturer do that a catalog supplier does not?

A custom O-ring manufacturer makes seals to your size, material, hardness or certification, usually by building a mold or using a splice process. A catalog supplier sells set sizes from stock. Choose custom when no standard size or compound fits your groove or service conditions.

What is the difference between silicone and rubber O-rings?

Silicone O-rings suit wide temperature ranges, food and medical contact, and static seals. Rubber O-rings in NBR, EPDM or FKM are usually better for oils, fuels, steam, aggressive chemicals and moving seals. The service conditions decide, not a default preference.

What are clear silicone O-rings used for?

Clear silicone O-rings are translucent silicone seals used where visual inspection, appearance or pigment-free material matters, such as food, beverage, laboratory and consumer equipment. Suppliers such as Canyon Components and Apple Rubber publish translucent silicone offers, and Best Seal lists transparent as a color option. Ask any supplier for the exact grade, cure system and certificates.

How do I choose the right O-ring material?

Start with the media the seal touches, the temperature range, the pressure and whether the seal moves. Then check the regulations for your market. Match these to a compound's data sheet, and request samples for testing before you place a production order.

Can I order custom O-rings from a drawing, photos or a sample?

Most custom manufacturers quote from a drawing, and many accept a physical sample. Vietnam Silicone Rubber states that it accepts orders from samples, drawings and custom dimensions, and its order process asks for photos or 3D drawings, size, thickness, color, silicone type, quantity and delivery time.

What should I know about OEM and ODM O-ring orders?

OEM means the supplier builds to your design. ODM means the supplier also helps develop or adapt the design. Vietnam Silicone Rubber lists OEM, ODM and private-label support on its facilities page. Before you commit, agree in writing on tooling ownership, minimum order quantity, sample approval and NDA terms.

Do custom O-rings always need new tooling?

Custom sizes outside standard dash numbers normally need a mold, though some very large rings are spliced or continuously molded from cord instead. Tooling adds lead time and cost, so ask each supplier for both before you approve samples.