Now you have a choice of momentary or constant-on light activation with out having to rotate the tailcap of your light. Push lightly on the tailcap for momentary activation without having to rotate the tailcap of your light. Push lightly on the tailcap for momentary activation, push harder to “click” the light into constant-on mode. Click again for off. Fits the following Surefire flashlights: 6P, 9P, C2, C3, G2, G2Z, Z2.