Measure radius of external arc, arc angle of measured surface should be larger than 90?
Resolution .0005″/0.01mm
Buttons: on/off, set, inch/mm, preset (+, -)
Automatic power off, move the digital unit to turn on power
Battery CR2032, Data outputMade of stainless steel
Supplied with pin gage for zero setting

3M 83539, Scotch Heavy Duty Packaging Tape Dispenser ST-181, Foam Handle with Retractable Blade, 7100288393
Dynabrade 91426 1/4" W x 12" L 80 Grit A/O DynaCut Belt, 50/pack
Dynabrade 78425 4-1/2" Dia. x 3/8" Coarse DynaBrite Surface Conditioning Disc, 25/pack
Dynabrade 78601 3/8" Dia. x 2" W x 1/8" Center Hole, 180 Grit, 100/pack
3M 33443, Cubitron II File Belt, 36+, 1/2 in x 18 in (12.7 mm x 457.2 mm), 7100033184, 10 belts per carton, 5 cartons per case 