Specifically designed to easily measure outside dimensions up to 1" including tube diameters, as well as accurately measuring wall thickness up to .08" simply by raising the oval tip rod. Spring loaded plunger guarantees repeatable pressure against the measured surface for more accurate reading. Long lasting corrosion free aluminum body.  Measuring tip diameter is 5mm.  3 button operation: on/off, Floating zero for easy direct reading of relative measurements, inch/metric conversion. Resolution: .0005" x 0.01mm Auto shut-off will turn off the gauge after 5 minutes of idle time.  Fitted in a plastic box with 2 SR44 batteries.

Outside Range:  0-1" x 0-25mm
Wall Thick Range:  0-.08" x 0-2mm
Reading:  .0005" x 0.01mm