This is a heavy duty vise. The head pivots up and down by loosening set screw with 3/16" hex wrench(not included). Included is a heavy duty clamp mount to attach your vise to a work surfaces up to 1-1/2" in thickness. The vise is a little tricky to adjust in the beginning, but once you have the cam ring adjusted, the vise is easy to work with. Jaws are removable, see other auction for FV2152 for compatible jaws. Accommodated hook sizes 2/0 to 22. Works with optional FV2148 and FV2149 pedestal bases.