Pony 2640 4-Inch C-Clamp Opening capacity is 4 inches Throat depth is 3 inches Load limit is 1,200 pounds Ideal for most do-it-yourself, woodworking and household clamping projects Adjustable Clamp Co. (founded 1903) is the manufacturer of the C-Clamps and they are assembled with U.S. and foreign parts in our Chicago factory