Hold machine,safety foot clamp,hydraulic pressure clamp,self-weight clamp The simply structured safety foot clamp is applicable in drilling less than 800 meters,including 53/55.5/71/89TK-3 hydraulic pressure clamp can reduce the intensity of work,including 53/55.5/71/89Consulting on the design princeple of foreign products,our company researched and developed sefl-weight clamp.It is applicable in ...