Yunsheng is the manufacturer offering API sucker rod coupling in Shandong China. All the rod coupling produced by API 11 B standard. These sucker rod coupling are very cost effective, including class SM sucker rod coupling, class T sucker rod coupling, Sub sucker rod coupling, Full Size coupling, Slim Hole coupling. They are available in 5/8”, 3/4”, 7/8”, 1” and 1-1/8”. Manufactured with high quality Carbon steel AISI 5I40 /4135. If you have any interests on our sucker rod coupling, please feel free to contact us for further information!