Digital Calipers

[Hogginhank]

Also check to see if caliper turns itself on when the sliding jaw moves ever so slightly. Mine does so I use the screw lock on top of the body to make sure it won't come on by itself. I went through a couple of batteries before I figured out why.

Yep. I went through the battery that came in the caliper and the extra battery before I figured that out as well. It is nice to have a few of them though. I keep one on my reel bench, one in my travel reel servicing kit and the 3rd one is in my reloading room