Usage Tips:Features: *1. : You can get a laser light. *2. Powerful usage: The laser light is powerful with the super clear and extra bright laser beam. *3. Easy to use: Windage and elevation can be adjusted with included wrenches. *4. Good material: The laser light is made of metal. Metal housing is compact, lightweight, and durable. *1. Tube diameter: About 17mm/0.67in *2. Length: About 57mm/2.24in *3. Tube size: About 48mm x 17mm/1.89 x 0.67in *4. Laser range: 50-100 Meter *5. Laser wavelength: 835-655mm *6. Mount size: Can adjust to 20mm or 11mm *7. Application: Construction instruction, astronomy, field adventure, meeting,etc Package includes: 1 * Laser sight scope+Base 2 * Wrenche 3 * Button cell