Slip-On Flashlight Bezel Filters 1.0 InchSureFire slip on filters add versatility to your WeaponLight Filters help to preserve user's scotopic vision Choose F05 (red) to help you read red light readable topographic maps, or F06 (blue) to identify fluid on dry surfaces SureFire F05 and F06 filters slip onto the bezels of select SureFire models. These filters can be flipped open and out of place when white light is needed. Both the red and blue colors can be used to preserve a user's scotopic