sucker rod coupling, rod joint, API 11b coupling class SM, T, UUS, full size&slime hole 45000pcs/month, ... T, SM, UUS, including sucker rod coupling, subcoupling, polished rod coupling,CROSS OVER coupling. Spraying Metal coupling combines top quality steel with a cold ... rolled thread that increase fatigue resistance. Our T and SM coupling are manufactured from high quality steel pipe in accord with ...