The BarrelCool Barrel Cooler & Indicator Flag is a unique patent approved product that combines the safety of a chamber flag and a fan for maximum barrel cooling on your rifle.BarrelCool fits right into the chamber of your Bolt-Action or AR Rifle. A powerful blower fan pushes air through your barrel, and returns it to ambient temperature, enabling you to shoot with more precision and accuracy.BarrelCool fits the standards for an NRA-approved chamber flag. Required at many ranges and competitions, a chamber flag indicates the firearm is free of any ammunition, and unable to fire. BarrelCool is a chamber flag that doubles as an enhancement for your rifle!Controlling barrel temperature is a known method to improve accuracy between strings. Enhance barrel cooling by using BarrelCool.(3) CR123A batteries included. Features Combines the safety of a chamber flag and a fan for maximum barrel cooling on your rifleFits right into the chamber of your Bolt-Action or AR RiflePushes air through ...