... BS, JIS, metric sizes all available. Description of Excellent Cat O-ring Kit PAHS Approved:1. Materials: can be NR ... tolerance: exactly upon your request or standard tolerance. 5. Color: black, transparent, green, red, yellow, grey, purple, pink thick ... , NSF, KTW, WRAS, LFGB, etc. 8. Applications: automobile cat o-ring kit, electrical appliance, mechanical, industrial, construction, household, medical ...