Catalog Hardware O-Rings and O-Ring Kits O-rings and O-ring kits help ensure a tight seal to prevent air and fluid leaks in applications such as air conditioner repair or plumbing installations. ◀◀ ◀ ▶ ▶▶ O-Ring: 36 mm Nominal Inside Dia., 43 mm Nominal Outside Dia., 43 mm Actual Outside Dia., 25 PK O-Ring: 44 mm Nominal Inside Dia., 52 mm Nominal Outside Dia., 52 mm Actual Outside Dia., Std, 25 PK O-Ring: 19 mm Nominal Inside Dia., 28 mm Nominal Outside Dia., 28 mm Actual Outside Dia., 10 PK O-Ring: 226, 2 in Nominal Inside Dia., 2 1/4 in Nominal Outside Dia., 60 Shore A, White, 2 PK O-Ring: 45 mm Nominal Inside Dia., 51 mm Nominal Outside Dia., 51 mm Actual Outside Dia., Std, 5 PK O-Ring: 178, 9 3/4 in Nominal Inside Dia., 9 15/16 in Nominal Outside Dia., 70 Shore A, Red, 10 PK Backup Ring, Contoured: Buna N, For 215, 0.05 in Thick, 0.174 in Radius, 100 PK O-Ring: 217, 1 3/16 in Nominal Inside Dia., 1 7/16 in Nominal Outside Dia., 75 Shore A, Black, 5 PK Backup Ring: Hytrel, For 236, 0.045 in Thick, Orange, 25 PK O-Ring: 220, 1 3/8 in Nominal Inside Dia., 1 5/8 in Nominal Outside Dia., 75 Shore A, Black, X, 5 PK O-Ring: 12.5 mm Nominal Inside Dia., 14.5 mm Nominal Outside Dia., 70 Shore A, Black, 50 PK O-Ring: 8.6 mm Nominal Inside Dia., 13.4 mm Nominal Outside Dia., 70 Shore A, Black, Metric, 100 PK O-Ring: 92 mm Nominal Inside Dia., 101 mm Nominal Outside Dia., 101 mm Actual Outside Dia., 2 PK O-Ring: 445, 8 in Nominal Inside Dia., 8 1/2 in Nominal Outside Dia., 70 Shore A, Black, Inch, 2 PK O-Ring: 137 mm Nominal Inside Dia., 145 mm Nominal Outside Dia., 145 mm Actual Outside Dia., Black O-Ring: 67 mm Nominal Inside Dia., 77 mm Nominal Outside Dia., 77 mm Actual Outside Dia., 75 Shore A O-Ring: 125 mm Nominal Inside Dia., 129 mm Nominal Outside Dia., 129 mm Actual Outside Dia., 2 PK O-Ring: 033, 2 in Nominal Inside Dia., 2 1/8 in Nominal Outside Dia., 90 Shore A, Black, Inch, 10 PK O-Ring: 474, 25 in Nominal Inside Dia., 25 1/2 in Nominal Outside Dia., 25.49 in Actual Outside Dia. O-Ring: 907, 7/16 in Nominal Outside Dia., 0.694 in Actual Outside Dia., 75 Shore A, Black, 25 PK ◀◀ ◀ ▶ ▶▶