• Length: 6 7 / 8 "/175 mm Shank dia.: 3 / 8 " x 7 / 8 " long 10 x 20 mm long • Feeler dia.: 1 / 8 " /3 mm • Measuring range: 0.25" of axis • Dial reading: 0 - 50 • Graduation: 0.0005" • Includes 6 Feelers: 4", 8", 12" Straight 4", 8", 12" Curved • Capacity: 5 / 32 " - 4 1 / 4 " internal 0 - 4 1 / 4 " external • Locating accuracy is 0.0005" of center • Operates at any angle from horizontal to vertical without any change, and from internal to external by simply changing the feeler • Supplied in a fitted wood case • This set includes: Indicator body, restraining rod (prevents rotation), spring-loaded center point feeler, three straight feelers (for IDs), three curved feelers (for ODs)