choke-line manifold working pressure: 2000PSI -20000PSI API 4130 45#, etc Inside nominal diameter: 52mm-103mm This drilling throttle valve is made of hard alloy, especially for valve plug and valve stem head, with strong performance of wear-resistant. Easy to use. choke-line manifoldworking pressure: 2000PSI -20000PSIAPI 4130 45#, etcinside nominal diameter: 52mm-103mm