Technical Data:
Digital external hook calipers
Measure width and distance of grooves inside bores
Non waterproof
Resolution: 0.01mm/0.0005in
Automatic power off, move the digital unit to turn on power
Battery: CR2032
Made of stainless steel
Buttons: on/off, zero, mm/inch
Range: 0-150mm/0-6in
Accuracy: +/-0.03mm

Dimensions:
L=275mm
b=14mm
e=52mm
f=50mm
Drawing dimensions (unlabeled)=7mm; 4mm; 16mm

Remark:
Built-in wireless; receiver code 7315-2/3/6/7/8/9 is needed