I have small wrists, and a couple nice straps that are just a wee too large. Don't want to ditch them. OK, need something to punch another hole.
Got this from Esslinger just now:
5 holes from 0.8 to 2mm. $25.
6.25 inch leather punch pliers
Used it on an ostritch strap. Worked just fine! Have to eyeball, and the new hole is just a bit too close to the one before, but not so anyone can notice. Clean hole, too.
So if you have problems getting straps to fit sometimes, this is handy.