30-30 Win Cartridge Caliber Red Dot Laser Bore Sight for Rifle by Golden Eye Tactical Convenient, accurate and easy to use. Compact, lightweight and durable. Reduces ammo waste. Range for Sighting: 15-100 yards. Best Range for Sighting: 20-30 yards. Total Length: 45.66mm (1.80" approx). Wavelength: 625-645nm, less than 5mw