The Modlite Weapon Mounted Light Body is designed as a direct replacement body for the Surefire Scout Light M600DF weapon light and the KE2-DF head. The Light Body is compatible with many tailcaps including Surefire z68, Modlite TCC Tailcaps, Surefire UE and DS00 tailcaps. It will also fits any aftermarket Scout mounts, as it retains the mounting holes and square lug interface on the underside of the light body.Note This light body accepts 18350 cells only. Lithium CR123 cells are not supported and if used will cause the cells to heat up and possibly explode or catch fire. Modlite recommends KeepPower high drain 18350 1200mAh cells. Runtime is about 35-40 minutes with these cells. The Modlite 18650 light body is NOT compatible with the Surefire older Scout light heads. Also please note this item is just a light body and it not a complete light.