irwin tools quick-grip 100 series deep throat c-clamp, 3-inch by 4 1/2-inch throat (225134)

Deep throat lets you use a smaller c-clamp on a larger project. Larger handle makes it easier to apply more clamping pressure with less hand fatigue.
Double-threaded screw reduces screw deflection and drift for faster clamping and allows you to apply 50% more clamping force than with most clamps.
C-clamp designed for woodworkers, carpenters, welders, builders, or do-it-yourselfers. Suitable for general clamping needs.
Larger swivel pad reduces marring on work surface and increases stability.