One counter reads in the plus direction and another in the minus directiion, so incremental measurement can be made in either direction
Carbide tipped scriber
Made of stainless steel (except the base).
With driving wheel. With dial test indicator holder.
Supplied with dust cover
Optional accessory: clamp for protracotors (code 2372-CLAMP)

3M 22392, Roloc Disc 361F, 24 YF-weight, TR, 3 in, Die R300V, 7000045090
Insize 7231, SCRIBER, 6928640320071
3M 85492, Scotch Foil Tape 3311-10A, 2.0 in x 10 yd (50.8 mm x 9,1 m), 7010383663 