The MSI-PRO 225-D 51120 toggle clamps, are sturdy and well made.  There are no sharp edges and the action is smooth.  The rubber foot has an adjustment range perpendicular to the clamp of about 1 1/8".  The slot in the clamp allows an adjustment of about 1 1/8" parallel to the clamp.  The base has holes for four 1/4" attachment bolts.  I drilled mine out to fit the 5/16" bolts I had on hand and didn't run into any problems.  The clamps will exert a lot of force which can be increased or decreased by raising and lowering the rubber foot.