api 5000API Specification 6A covers wellhead and tree equipment as follows: API Specification 6A Wellhead Equipment Valves, Chokes, and Actuators Plugs, Connectors, and Gaskets Otherapi 6a - type - 6b 34.5 mpa (5000 psi) gbt 22513-2013 API 6A-TYPE-6B 34.5MPA (5000PSI)