JIS B2401 is a Japanese industrial standard for O-ring sizes, set by the Japanese Standards Association. This standard groups O-rings into two main series: the P series, which is designed for moving parts such as pistons and rods, and the G series, which is designed for fixed sealing on flat or cylindrical surfaces.
The standard clearly defines the inner diameter, outer diameter, wire diameter, and groove dimensions for each size. JIS B2401 O-rings are widely used throughout Japan and across Asia in machinery, automotive, hydraulic, and general industrial equipment.
ZSR Silicone manufactures silicone O-rings that fully match JIS B2401 standard sizes, covering both the P series and G series. If your equipment follows Japanese design specifications or you need to replace seals in machines built for the Asian market, we can supply the correct JIS B2401 size in the silicone material that fits your application.
Simple JIS B2401 O-rings Size Chart
JIS B2401 Standard No. Range | CS (mm) | ID Range (mm) | OD Range (mm) | CS (inch) | ID Range (inch) | OD Range (inch) |
|---|---|---|---|---|---|---|
S3~22 | 1.50 | 2.50 ~ 21.50 | 5.50 ~ 24.50 | 0.059 | 0.098 ~ 0.846 | 0.217 ~ 0.965 |
S22.4~150 | 2.00 | 21.90 ~ 149.50 | 25.90 ~ 153.50 | 0.079 | 0.862 ~ 5.886 | 1.020 ~ 6.043 |
P3~10 | 1.90 | 2.80 ~ 9.80 | 6.60 ~ 13.60 | 0.075 | 0.110 ~ 0.386 | 0.260 ~ 0.535 |
P10~22 | 2.40 | 9.80 ~ 21.80 | 14.60 ~ 26.60 | 0.094 | 0.386 ~ 0.858 | 0.575 ~ 1.047 |
P22~50 | 3.50 | 21.70 ~ 49.70 | 28.70 ~ 56.70 | 0.138 | 0.854 ~ 1.957 | 1.130 ~ 2.232 |
G20~145 | 3.10 | 19.40 ~ 144.40 | 25.60 ~ 150.60 | 0.122 | 0.764 ~ 5.685 | 1.008 ~ 5.929 |
V10~15, V24, V34, V40, V55~58, V70, V85, V100, V120, V140, V150, V175 | 4.00 | 9.50 ~ 173.00 | 17.50 ~ 181.00 | 0.157 | 0.374 ~ 6.811 | 0.689 ~ 7.126 |
P48~150 | 5.70 | 47.60 ~ 149.60 | 59.00 ~ 161.00 | 0.224 | 1.874 ~ 5.890 | 2.323 ~ 6.339 |
G150~500, G510, G520~560, G570, G580~590, G600~605, G615~620, G630, G860, G910 | 5.70 | 149.30 ~ 909.30 | 160.70 ~ 920.70 | 0.224 | 5.878 ~ 35.799 | 6.327 ~ 36.248 |
V225, V275, V315, V325, V380, V430, V475 | 6.00 | 222.50 ~ 470.50 | 234.50 ~ 482.50 | 0.236 | 8.760 ~ 18.524 | 9.232 ~ 19.000 |
P150~505, P545, P590~600, P610, P620~625, P635, P650, P680, P690, P700, P710, P720, P730, P740, P750, P760, P770, P780, P790, P800, P810, P820, P830, P840, P850, P860, P870, P880, P890, P900, P910~920, P930, P940, P950, P960, P970, P980, P990, P1000 | 8.40 | 149.50 ~ 999.50 | 166.30 ~ 1016.30 | 0.331 | 5.886 ~ 39.350 | 6.547 ~ 40.012 |
V480, V490, V510, V530, V585, V640, V690, V740, V790, V845, V950, V1055 | 10.00 | 475.00 ~ 1044.00 | 495.00 ~ 1064.00 | 0.394 | 18.701 ~ 41.102 | 19.488 ~ 41.890 |