Fast and easy way to check barrels for cleaning or wear. Insert the short end of the UV bore light Illuminator into the firearm chamber and watch the fiber optic tool light up your bore for inspection. No batteries needed, our UV bore light Illuminators are ready anytime, whether you are at home or in the field. Features: Can be used as a chamber flag for most calibers Illuminates bore with ambient light Illumination can be enhanced by flashlight Made in the USA