INSIZE 4166-7 Steel Pin Gauge Set 6.50–7.00 mm

INSIZE's 4166-7 pin gauge set spans 6.50–7.00 mm in 51 steel pins, each 0.01 mm apart. INSIZE rates the set to DIN 2269, grade 1 and ±1 µm diameter accuracy; the pins are alloy steel, hardened to HRC62-65. The pins measure 50 mm in length and come housed in a lined wooden case for storage. Inspectors use sets like this to gauge hole and bore diameters by hand, trying successive pins until one seats correctly and reading the size off its handle.