Materials: Compatible with all transparent and colored lenses. ABS+stainless steel, color temperature 6000K, battery model CRI >80, brightness 300 lumens, charging model CRI >85, brightness 400 lumens. Adjustable Light Source: Battery type button adjustment, three levels of brightness. Power supply: 2 AA dry batteries (need to be purchased by yourself). The charging knob has stepless adjustment of gears and colors. Power supply: 3.7V 2200mAH polymer lithium battery. Uniform Brightness: You can observe the light and dark stripes of the lens, the force distribution during the injection molding process, and check the changes in the installation force and the differences between real and fake crystal lenses. Easy To Use: Place the glasses to be tested between the analyzer and polarizer of the stress meter, Observe the lens peripheral stress in the lens ring from top to bottom, then judge the uniformity of stress distribution around the lens. Multifunctional Application: Comes with a polarizer function for identifying gemstones like diamonds. It serves as a practical auxiliary testing instrument and professional tool for transparent gemstone inspection.