These are replacement pads for Irwin Quick Grip clamps.  Printed in TPU flexible filament, these will not mar the surface of what you're clamping (just like the originals).

I used Sainsmart TPU but any flexible filament will work. In order to get a smooth face surface, I set perimeters to 4 in PrusaSlicer. If I used infill, there were little bumps on the face. Probably not a problem, but for the few extra minutes of print time and feet of filament it was worth it. 

Print this with the “end” down and you don't need any supports,