We are offering air operated hold down clamp. As: it has a u-bar arm and flanged washers for easy lateral or vertical positioning of the spindle which can be moved to any desired position along the "u" arm. sb: it has a solid hold-down square bar arm which can easily cut off, drilled and tapped for adjustment spindle of the welding of special adopters. all hold-down arms opened at 90 degree all air cylinder are double action.