Track's bore gauge is a rugged solid brass tool, engraved on one side from .015 to .80 caliber, with all popular calibers accurately marked for easy inspection. A blank area is suitable for engraving.
The reverse side is marked with popular shotgun bore sizes, from .410 to 10 gauge along one edge. The other edge is calibrated in metric bore sizes, from 5.5 mm to 11 mm, with all the popular metric calibers (6.5 mm, 7.65 mm, 9 mm, etc.) clearly marked.
Carry it to your next gun show. You'll be surprised how handy it is, and how often bore size is in doubt.
Punched for a lanyard, this nice brass gauge would make a shandy key chain accessory, or gentleman match shooter's pocket watch fob.