Brief Introduction : 1.high quality alloy steel processing, light weight, small size, big load, greatly reduce the work intensity. 2.composed of main parts, hand door, lock pin assembly and hand shank etc. through technological transformation, the users can easily confirm the hand door open or not and greatly reduce the occurrence of safety accidence. 3.double proofed safety pin has been invented after many years reaserch and practical operation, which have obtained good reputation from the oilfield workers. We are a professional manufacturer of oil down hole tools , high quality and reasonable price . Any problem about our products , welcome here .