... . Quantity can be made on customers demand.Material :Tungsten Carbide,Ceramic,Metal.Quality character: roughness ≤ Ra0.20mm density ≥6.0g/cm3 ... , coefficient of friction is 0.1 Product precision: ±1 µm, ±2 µm, ±5µm. Diameter: 1mm~30mm Length: 30mm, 40mm, 50mm Pack: in ... and to measure the depth of the hole. As zirconia ceramic pin gauges/plug gauges are chemically inert and environment friendly ...