... -speed DSP chip, have fast measurement abil Digital Coating Thickness Gauge InstructionsDescriptions:AT220,AT230, AT240 these instruments ... metal matrix,such as paint,a variety of anti-corrosion coating powders, plastic, rubber, synthetic materials, phosphide layer, chromium ... metal matrix,such as paint,a variety of anti-corrosion coating powders, plastic, rubber, synthetic materials, phosphide layer, ...