●This is an IR filter that can be installed on Surefire Scoutlite series, such as the M300A M300B M300C M600B M600C. It is also recommended as a dress up part, as it makes a cool look ●The cap has a selective IR (Infrared) filter that allows you to use the powerful LED light as a light source when using the night vision goggles. The light source is red Also, the IR filter features are limited ●The cap can be tightened to protect your precious light lens from bullets. Also recommended as a lens cap/lens protector ●The IR filter simply raise the lever, insert into the light and knock the lever. Easy to install without any tools ●Resin body has a slightly textured matte black finish. Even if you wear it with the actual product, you can wear it without any discomfort