A drift punch, or drift pin, is used as an aid in aligning bolt or rivet holes prior to inserting a fastener.

A drift punch is constructed as a tapered rod, with the hammer acting on the large end of the taper.

The tapered end of a drift punch is placed into the semi-aligned bolt holes of two separate components, and then driven into the hole.

As it is driven in, the taper forces the two components into alignment, allowing for easy insertion of the fastener.

drift brass and bronze tapered