Surface Roughness Comparator No.130 Composite Set, This Set Consists Of 30 Comparison Sp Ecimens, Covering Six Of The Most Commonly-Used Machining Methods: 6 Cylindrically Turned, 6 End-Milled, 6 Horizontally Milled, 6 Surface-Ground, 3 Lapped, 3 Reamed/Drilled.Make: Rubert Model No. 130: Or Miyuto Yo Or Sylvac [ Warranty Period: 30 Months After The Date Of Delivery ] ]