Standard AS568 O-ring
AS568-421 O-Ring, 3.975 x 0.275 in (100.97 x 6.99 mm)
The AS568-421 O-ring (dash 421, also written 2-421) has an inside diameter of 3.975 in (100.97 mm), a cross section of 0.275 in (6.99 mm), nominal 1/4 inch, and an outside diameter of 4.525 in (114.95 mm). We supply it in Buna-N (nitrile), Viton (FKM) or EPDM, in packs of 10, 25 and 100.
Size
| AS568 size | -421 |
|---|---|
| Inside diameter (ID) | 3.975 in (100.97 mm) |
| Cross section (CS) | 0.275 in (6.99 mm), nominal 1/4 in |
| Outside diameter (OD) | 4.525 in (114.95 mm) |
Rubber and pack prices
| Rubber | 10-pack | 25-pack | 100-pack |
|---|---|---|---|
| Buna-N (nitrile) 70AGood for water, air and petroleum oils; the usual choice for filter housings. | $8.99 | $21.99 | Request a quote |
| Viton (FKM) 75AGood for heat, fuels and many chemicals. | $33.99 | Request a quote | Request a quote |
| EPDM 70AGood for hot water, steam and chlorinated or chloraminated water. | $15.99 | $44.99 | Request a quote |
A size match is not a fit claim for your equipment. Some sizes ship from stock; others have a 2-3 business day lead time before they ship. Not for oxygen, medical, aviation, scuba or other safety-critical use.