Regular duty (CDF) extra deep throat C-clamps with a black frame and a black oxide spindle that resist corrosion. It has a ball-in-swivel pad and powder coated frame.
From the Manufacturer
Drop Forged, Heat Treated Steel Frames, Black Oxide Coated Spindle & Swivel Pad to Resist Corrosion. 4" Capacity x 2--3/4" Throat Depth.