Spark-Duty™ 400P/400CS Hi-Vis C-Clamp, Sliding Pin, 4-1/8 in Throat Depth, Gray, 0 in to 6-1/16 in OpeningManufactured with drop forged steel for greater strength in standard applications V grooved anvil feature allows secure holding of all materials including rounds, squares, and flats Acme rolled spindle threads provide continuous smooth operation for faster clamping action and maximum strength Spindles and Perma Pads are copper plated to provide resistance to welding spatter and corrosion Ideal for industrial welders and steel fabrication