1.875-2.875" Internal Dial Caliper Gage Graduation is 0.001". Arm thickness is 0.09". Arm length is 3.25". Carbide ball measuring points are 0.09" x 0.09". This gage has a button you push to close the arms. 0-1" movement to check recessed diameters, internal bores, etc. Set with micrometers or a ring gage. Bezel can be rotated for zero setting and can be locked with screw. Shipping Weight: 0.9 lbs