This brand new Evike Eagle Force tracer unit hasn’t seen a single BB fired through it. I put AAA batteries into it, dropped a BB manually through it to test LED function. I then placed it on my rifle took a picture and decided it is way too long for my needs. The tracer unit attaches to any birdcage flash hider, using tightening ball bearings in order to clamp down on said flash hider. All I have done with the unit has been opening the package, adding batteries, putting it on and off of my gun, and closing the package. If you have any questions please ask. I’m happy to help. Price includes shipping, 4 AAA batteries and the unit itself. Thanks for looking.