Buna-N Back-Ups 90 Durometer Rings

• O-Ring Sizing Chart (PDF)
• O-Ring Material Guide (PDF)

Master Item #	Actual Size I.D. (in)	Actual Size I.D. (mm)	Actual Size I.D. Tolerance (in)	Actual Size I.D. Tolerance (mm)	Actual Size W. (in)	Actual Size W. (mm)	Actual Size W. Tolerance (in)	Actual Size W. Tolerance (mm)
AS 568A-326	1.6	40.64	±.015	±0.38	0.21	5.33	±.005	±0.13
AS 568A-327	1.725	43.82	±.015	±0.38	0.21	5.33	±.005	±0.13
AS 568A-328	1.85	46.99	±.015	±0.38	0.21	5.33	±.005	±0.13
AS 568A-329	1.975	50.17	±.018	±0.46	0.21	5.33	±.005	±0.13
AS 568A-330	2.1	53.34	±.018	±0.46	0.21	5.33	±.005	±0.13
AS 568A-331	2.225	56.52	±.018	±0.46	0.21	5.33	±.005	±0.13
AS 568A-332	2.35	59.69	±.018	±0.46	0.21	5.33	±.005	±0.13
AS 568A-333	2.475	62.87	±.020	±0.51	0.21	5.33	±.005	±0.13
AS 568A-334	2.6	66.04	±.020	±0.51	0.21	5.33	±.005	±0.13
AS 568A-335	2.725	69.22	±.020	±0.51	0.21	5.33	±.005	±0.13
AS 568A-336	2.85	72.39	±.020	±0.51	0.21	5.33	±.005	±0.13
AS 568A-337	2.975	75.57	±.024	±0.61	0.21	5.33	±.005	±0.13
AS 568A-338	3.1	78.74	±.024	±0.61	0.21	5.33	±.005	±0.13
AS 568A-339	3.225	81.92	±.024	±0.61	0.21	5.33	±.005	±0.13
AS 568A-340	3.35	85.09	±.024	±0.61	0.21	5.33	±.005	±0.13
AS 568A-341	3.475	88.27	±.024	±0.61	0.21	5.33	±.005	±0.13
AS 568A-342	3.6	91.44	±.028	±0.71	0.21	5.33	±.005	±0.13
AS 568A-343	3.725	94.62	±.028	±0.71	0.21	5.33	±.005	±0.13
AS 568A-344	3.85	97.79	±.028	±0.71	0.21	5.33	±.005	±0.13
AS 568A-345	3.975	100.97	±.028	±0.71	0.21	5.33	±.005	±0.13
AS 568A-346	4.1	104.14	±.028	±0.71	0.21	5.33	±.005	±0.13
AS 568A-347	4.225	107.32	±.030	±0.76	0.21	5.33	±.005	±0.13
AS 568A-348	4.35	110.49	±.030	±0.76	0.21	5.33	±.005	±0.13
AS 568A-349	4.475	113.67	±.030	±0.76	0.21	5.33	±.005	±0.13
AS 568A-350	4.6	116.84	±.030	±0.76	0.21	5.33	±.005	±0.13