... , P, R, S, T, UProduct specification level PSL1, PSL2, PSL3Product performance level PR1, PR2Working medium can be hydrogen sulfide in ... models.*There are also special lightweight models for airlifting and Arctic models for low temperature service.SPECIAL FEATURES — ... long stripping life.USAGE:•Annular blowout preventer uses and hydraulic control systems supporting the use of, when within the well ...