Brass Laser Bore Sight Cartridge Red Laser Boresighter For 243/308WIN This 308 7.62x51 .243 Laser Bore Sighter features precision accuracy. This bore sighter is a fast、 reliable and durable gun zeroing and sighting system.Features: Precision accuracy. Reliable and durable. Fastest gun zeroing and sighting system. Reduce wasted cartridges and shells. Compact and lightweight. Easy to pack and travel. Laser wavelength (nm): 635-655nm LED type: Visible red laser Power: Less than 5mW Off axis angle: 0.1mrad (high precision) Battery type: LR41 Operation: On/off end cap Construction: Brass Temperature: 10-50≧ Package included: 1 x Laser Boresighter 3 x Batteries 1 x User Manual Net Weight: 40g