dimension; thrice; F pc; mobile phone test instruments; X-ray thickness-measuring meter; f pc testing instrument; F pc testing instrument; mobile phone turndown cap testing instrument; mobile phone testing instrument; RCA paper tape testing machine; Projector; microscope; muller; TESA measuring tools; peel off strength testing instrument; push-button switch- displacement curve testing machine; Contact insertion and withdraw force tester; alcohol abrasion performance testing machine; C cd online detecter