Standard and metric oring sizes in stock. Large inventory of buna nitrile o-ring, silicone o-ring, epdm o-ring and viton o-ring sizes. We also supply a wide range of mil-spec o-rings. And for serious demanding service, we offer perfluoroelastomer o-rings including Chemraz®, Kalrez® and Simriz® o-rings.

Shown at right are some of the various o-ring and related products carried and a list of list of common standard and military spec materials. Click on a link for more information.


Quick Links:

O-Ring Sizing Chart



O-Rings, O-Ring Kits, Mil Spec Viton Orings and More

viton o-ring

Standard, metric and custom o-rings offered in a full range of commercial and mil-spec compounds including Viton, Buna, Silicone, Perfluoroelastomer and others listed below. Common certified military specifications include AMS7276 (M83248/1) Fluorocarbon, AS3582 Silicone and Mil-P-25732 Nitrile.

backup rings

Buna and Teflon® back-up rings. PTFE (Teflon) backups are available as
solid, split and spiral backup rings.

quad rings

Standard o-ring dimensions with four sealing surfaces available in
Buna and Viton.

sqare o-rings

Standard o-ring dimensions with a square cross section configuration.
Commonly available in Buna material.

viton o-rings

Spliced and vulcanized custom size o-rings to nearly any dimension.
Just specify cross section and ID.

o-ring cord

Standard and metric cross sections in buna and viton o-ring cord stock. Silicone o-ring cord and other materials are also available in inch sizes.

o-ring kit

Oring Kits provide a convenient assortment of common sizes.  Standard o-ring kits, metric o-ring kits, splicing kits, quad kits and more.  Click the Link for more info.

o-ring sizing chart

Available here is a PDF format o-ring sizing chart showing o-ring dimensions for standard size o-rings. It is grouped by cross section and sorted by inside diameter.

o-ring lube

Lubricants are often used in o-ring assembly to prevent damage, to help seat the o-ring and can offer protection as a surface film. Parker offers a standard o-lube as well as a super o-lube. Click the o-ring lubricant link above for more info.

Standard O-Ring Compounds


Common Mil Spec Compounds

AMS7276 O-Ring (AMS 7276, AS3208, AS3209), M83248/1, Mil-R-83248/1 O-Rings:
75-Duro Black Fluorocarbon O-Ring


AMS7259 (AS3581), M83248/2
Mil-R-83248/2 O-Rings:
90 Duro Black Fluorocarbon O-Ring


AMS-R-83485 (M83485/1):
75 Duro Black Fluorocarbon O-Ring
GLT® Type Viton O-Ring


AMS-R-25988 CL 1 GR 70 (M25988/1):
Fluorosilicone O-Ring


AMS7267, AMS3304 (AS9385, AS9386, AS3582):
70 Duro Red Silicone O-Ring


AMS7257:Perfluoroelastomer O-Ring


Mil-P-83461 O-Rings:Nitrile


Mil-P-25732C (MS28775): Nitrile

Available O-Ring Compounds and Typical Properties

      Click on a compound link for further details
Compound Also knows as Key Characteristics Available Specs Avg. Temp Range (F)
Aflas Tetrafluoroethylene / Propylene Resistante to a wide range of chemicals.   -15°- 450°
Ethylene Propylene Ethylene propylene diene rubber, EPDM, EP, EPM, EPR Excellent resistance to ozone, weathering, steam, water and phosphate ester type hydraulic fluids. NAS 1613, NSF 61, FDA -70°- 250°
Fluorocarbon Viton ® , Fluorel ® , Fluoroelastomer, FKM Excellent resistance to high temperature and a wide range of chemicals. AMS 7276, AMS 7259, AMS-R-83248 (Mil-R-83248), AMS-R-83485, GLT Type, V0747-75 -15°- 400°
Fluorosilicone Fluorinated Polysiloxane, FVMQ Similar physical properties to silicone rubber with better fuel and mineral oil resistance but poor hot air resistance. AMS-R-25988, Mil-R-25988, M25988/1 -90°- 350°
Hydrogenated Nitrile Hydrogenated Acrylonitrile-butadiene, HNBR, HSN Improved fuel and ozone resistance over Nitrile. Often used in refrigeration systems.   -25°- 300°
Neoprene Chloroprene, CR Good ozone, aging and chemical resistance. AMS 3208, AMS 3209 -35°- 225°
Nitrile (Buna) Acrylonitrile-butadiene Rubber, Buna-N, NBR Most common general purpose elastomer. Good for petroleum fluids.

M83461/1, Mil-P-83461
AS3578, MS9021, AMS7271
MIL-G-21569, AMS 7272

MIL-P-25732, N674-70

-30°- 225°
PTFE Teflon ® , Polytetrafluoroethylene Chemically inert to most substances. Excellent resistance to high temperature. Extremely low coefficiant of friction   -65°- 500°
Perfluoroelastomer Kalrez ® , Simriz ® ,
Chemraz ® , FFKM
Excellent chemical resistance and high temperature stability. AMS7257 5°- 525°
Polyurethane Polyester or Polyether Urethane, PU, AU, EU Excellent wear resistance and high tensile strength. Good for Drive Belts.   -40°- 180°
Silicone Polysiloxane, VMQ, PVMQ Good heat resistance, cold flexibility and insulating properties. Low tensile strength and poor tear and wear resistance. ZZ-R-765, A-A-59588, AMS 3320, AMS 7267, AMS 3301, 3302, 3303, 3304, 3305,
AMS 3337, AMS 3357
-60°- 400°
Other Stock Rubber Materials
Cork Sheet, Cork and Rubber (AMS-C-6183), Cloth Inserted Sheet, Diaphragm Sheet (Nylon Insert), FDA Rubber, Hypalon ® , Masticated Rubber
Non-Asbestos Sheet, Pure Gum (Natural Rubber), SBR, Vegetable Fiber (Paper, Vellumoid, Plant Fiber)
Rubber Sponge and Foam
Closed Cell Sponge: Neoprene, EPDM Sponge, Vinyl Sponge, Silicone Sponge
Open Cell Sponge: Neoprene Sponge, Natural Open Cell
Foam: Microcellular Urethane, Poron, Silicone Foam, Charcoal Ester
Military Spec: Mil-R-6130 Sponge, ASTM D6576 Sponge, AMS 3195 Sponge (Silicone), AMS 3196 Sponge (Silicone)

The information contained here is for reference only. It is believed to be reliable, but no representations, guarantees or warranties of any kind are made to it's accuracy or suitability for any particular purpose. It is recommended that users conduct their own evaluations for the intended application.

Viton and Kalrez are registered trademarks of DuPont Dow Elastomers
Teflon is a registered trademark of DuPont
Chemraz is a registered trademark of Green Tweed
Simriz is a registered trademark of Simrit
Aflas is a registered trademark of 3M Company