C100BOP Series Couplings are compliant with the ISO-7241-B standard. Couplings machined from solid carbon steel come standard with buna-N (Nitrile) seals. C100BOP Series Quick Couplings are designed for use with blow-out preventer systems on drilling rigs. The red colour on both the coupler and the nipple designates that these couplings are B.O.P. fire approved and have been fire tested to 700°C and Lloyds witnessed to meet the API 16D standard.