... , with various spec. of Full size, Slim Hole, grand chamfer, Two-way camber, etc. With world top level equipments and technicians ... Sucker Rod Coupling5/8” FULL SIZE SPRAY METAL COUPLING WITH TWO WRENCH FLATSSIZEO.D.I.D.LengthWeightWrench Flat(L×W)SM ... /4", 7/8", 1", 1.1/8"USAGEJOINNING TWO SUCKER RODS TOGETHER FOR DOWNHOLEOIL PUMPINGLIFE-SPANAt least 6 monthsBASIC HARDNESS HRC 16 ...