These compact pneumatic swing clamps swing into position and clamp straight down onto the workpiece for direct downward pressure. The arm swings completely out of the way to allow for easy loading and unloading of the workpiece. Clearance between clamping spindle and workpiece should be roughly half of the clamping stroke. The clamp art swings horizontally. Ideal for repetitive clamping operations. Comes with a contact bolt that can be reversed for finished or rough surfaces. Mounts from the top with two mounting holes. Part numbers with R have a clockwise clamping direction, part numbers with L have a counter clockwise clamping direction. The body, clamp arm and piston are made from 4140 steel with an electroless nickel plated finish. The clamping spindle is made from 1045 steel, quenched and tempered, with an electroless nickel plated finish. The electroless nickel plating provides improved corrosion and wear resistance to increase the life of the clamp in harsh environments.