Dead Blow Mallets

A good source for these is anyplace that sells auto body working
supplies (better auto part stores), or even home depot or lowes (or
the equivalent).

It will be the same tool without the “jeweler’s tool” markup.

Some are made of an impact absorbing material, others are filled with
shot so that they don’t bounce easily.

Ron Charlotte -- Gainesville, FL OR @Ron_Charlotte

The ones sold by auto body suppliers are not the same. Those are
Compothane, a different material with a compothane handle. I used to
use that type, but found that the jewelers model is far superior. Alan