Sucker rod coupling Two types of coupling are available which meet api specifications: regular api class t coupling and spray metal coupling for anti corrosion. Our couplings include sucker rod coupling, subcoupling, and polished rod coupling with different size specification. 1) material: seamless alloy steel 2) standard: api spec 11b 3) class: t sm 4) main specification: 5/8", 3/4", 7/8", 1", 1 1/8" 1000pcs, 750kg, 1200*720*360mm
