Mitutoyo's Dial Bore Gage offers interchangeable anvils and necessary accessories to perform close tolerance I.D. measurements. Carbide ball contact point for durability. Optional extension rods can be attached. A Digimatic Indicator can be attached in place of the dial gage. Specifications include... 0.7" - 1.40" Measuring Range 0.0001" Graduations (2923SB-10 Dial Indicator) Accuracy: .0008" 2 Spacers 9 Anvils