LP021B Red laser diode beam. Wavelength: 650nm. Max output: 5mW. 1 red laser beam. Output mode: Constant Wave. Pressure button for laser beam. Batteries type: two AAA Alkaline batteries (Not included). Useful kit for office or school presentation. Best choice of gift for your family or friends. Package Details Weight: 28.89 g Size: 13*1*13 cm Package Includes 1 × HJ-142 Red Laser Pointer