Tiablo Anti-Spill will reduce overspill of light and concentrate the beam when used with most flashlights with head diameter of 57mm. Type-III hard anodize high quality aerospace grade T7075 aluminum construction made to tough to last.  An excellent add-on for Tiablo A10-G, A50G, and ACE-G. Add filters to the Anti-Spill to make your flashlight an excellent tool for hunting at night, and for military and police applications.