Insize ISR-CSE317, SURFACE ROUGHNESS SPECIMEN, 8pcs per set, 6928640376580

Machining method: flat lapping criss-cross.
Ra: .1, 2, 4, 8,16,32,63,125_in. Rz: 16,24,30,50/14,22,45,60_in.
For checking, identifying and specifying the roughness by symbol.
Rust-proof, made of pure Nickel.