Warning: 1. Never point at eyes!!! 2. Always keep away from children!!! 3. Don't keep leave the unit on for a long time; otherwise it will damage the light bulb.Specifications:��Model: SDLaser 303 Type: Pen Laser Color: GreenLaser range: 6562-16404 feet/2000-5000 meters Focus: AdjustableDimensions: ��13.5 * 167MMOutput wavelength: 532 nmOutput power: 5mW Class��BCircuit control: APC linesOperating Voltage: DC = 3VWorking Current: I <450mAWarm-up time: NoneWorking temperature: + 20 �� ~ + 30 ��Storage temperature: + 10 �� ~ + 40 ��Power supply: two AAA alkaline batteriesStructural features: laser tube + crystal + lens groupColor: black rubber barrel roast， other parts are hanging white chrome!Usage:The front end of the rotation of the optical interface can be adjusted at different points like stars effects， you can unscrew the head， you can use when ordinary green pen， which is the issue of the green line， used to refer magnitude.Package Include:1 x Green laser pointer2 x Safety Key1 x Battery Charger1 x lithium Battery1 x Strap