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

Dynabrade 90873 2" Dia. Medium NWN DynaBrite Locking-Type Disc, 25/pack
Norton 66254414832 - 3" X 1/4" X 1/4" Vortex Rapid Blend Unified Wheel, 5am U2305, 40 Each
Norton 66261014792 - 2" Medium Grade Aluminum Oxide Bear-Tex Speed-Lok High Strength Maroon TR Non-Woven Abrasive Disc 160 Each
3M 19764, Utility Cloth Sheet 314D, 9 in x 11 in P320 J-weight, 7000000352
Insize 6315, MICROMETER MEASURING FORCE DETECTOR, 6928640351143
3M 17083, Versaflo Hood with Integrated Head Suspension, S-433L-5, Medium/Large, 7000029981, 5 EA/Case
3M 19772, Utility Cloth Sheet 314D, 9 in x 11 in P80 J-weight, 7000000359
Standard Abrasives 713276, Aluminum Oxide Handy Roll, P180 J-weight, 2 in x 50 yd, 7100037246
3M 26118, PPS Series 2.0 Adapter, Type S26, 11 mm Male, 1.0 mm Thread, 7100135924
Standard Abrasives 714179, Aluminum Oxide Handy Roll, P240 J-weight, 1-1/2 in x 50 yd, 7100050575
Air Turbine Tools 310RSV - 1/4" Router Hand Tool Series, 40,000RPM, 33440
3M 22407, Roloc Disc 361F, 80 YF-weight, TR, 1-1/2 in, Die R150S, 7000045099
3M 19766, Utility Cloth Sheet 314D, 9 in x 11 in P240 J-weight, 7000000354
3M 05009, Utility Cloth Roll 211K, 100 J-weight, 1 in x 50 yd, Full-flex, 7100016843 