Precision, inside dial caliper gives the gunsmith the right tool to accurately measure chambers, choke tubes, bores and various other inside dimensions in the gun shop. Easy-to-read dial is graduated to handle measurements from .375"–1.375" with .001" accuracy. Aluminum housing with bezel locking screw lets you set zero for comparative measurements. Small needle measures tenths of an inch, large needle records thousandths. Push-button on the side closes the caliper arms so you can insert the caliper into the area to be measured. Ball bearing contact points deliver true, repeatable measurements every time.