... . API 11B standard 2.Material: 4120,4142,4330,4720,4620 3. Sinter bar,polished rod and subcoupling are avaiable. Description : Our Sucker rod ... produced according to API 11B specification.The material is in Grade C, D ... , K, KD,H,I, HL, HY Specification parameter of sucker rodNominal ...