... /BV /ISO /DQS /API /AAA Hollow Pin Conveyor Chains (MC Series):Why choose us ?1. Hangzhou Donghua Chain Group Co., Ltd established in 1991 ... as A or B series chains, roller chains, driving chains, conveyor chains, hoisting chains, agricultural chains, sprockets and so on; 4 ... and the step of technology reform. It intends to produce high strength and precision chains in order to meet requirements of ...