Dial in your accuracy and eliminate guesswork with the Sightmark .300 Winchester Magnum Laser Bore Sighter-a must-have tool for hunters long-range shooters and precision marksmen.Engineered for efficiency and pinpoint accuracy this in-chamber laser bore sighter allows you to align your optics quickly and reliably saving both time and ammunition.Crafted from durable high-grade brass this bore sighter is specifically designed for the .300 Win Mag caliber ensuring a secure and precise fit inside your rifle's chamber.The high-visibility laser projects a crisp beam downrange helping you achieve on-target calibration before firing a single live round.Whether you're initially sighting in a new optic checking zero after travel or using it as a training aid for dry-fire or quick-draw drills the Sightmark Laser Bore Sighter delivers consistent performance in the field or at the range.Compact and lightweight for maximum portability it comes packaged with 3 AG3 batteries and a protective carrying case making it easy to pack transport and deploy wherever your shooting adventures take you.Features / SpecsSightmarkSM39006Chamber Laser Bore Sight.300 Winchester MagnumLaser Wavelength: 632 - 650 nmLED Type: Visible red laserOutput Power: 5 mWBattery Type: AG5 (2)Battery Type: AG3 (3)Battery Life: 1 hourRange for Sighting: 15 - 100 ydsDot Size: 2 in @100ydOperation: On/off end capMaterial: BrassOperating Temp F: 14 to 122IncludesCarrying caseInstructions