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 17528 Scotch-Brite Surface Conditioning Low Stretch Belt, SC-BL, A/O Very Fine, 1-1/2 in x 60 in, 7010292405
3M 19768, Utility Cloth Sheet 314D, 9 in x 11 in P180 J-weight, 7000000356
Insize 7341-15S, PIN GAGE HANDLE (with 1pc handle and 8 pairs of collecting bushes), .760-1.010", 6928640396847
3M 01875, Charge-Collection Solar Tape 3011, 2 mm x 1200 m, 7010312686 