Insize ISR-CSE130, SURFACE ROUGHNESS SPECIMEN SET, 30pcs per set, 6928640376504

For checking, identifying and specifying the roughness by symbol.
Accuracy: +20% ~ -25%, Ra<0.1_m. Accuracy: +12% ~ -17%, Ra>0.1_m.
Meets ISO 2632.
Rust-proof, made of pure Nickel.