Seismic Audio - Set of 8 Rubber Feet Guitar Amp Case Speaker Cabinet DJ - Replacements
I purchased these rubber feet from Seismic Audio on Amazon.  They were replacement for feet on a set of Bose 901s.  They fit perfect with a recessed hole for the screw. Rubber is hard but grip well on a smooth surface so the speakers don't move. Quality was excellent.  Seismic Audio delivery was quick.