This is a twist-type flashing tail cap from NEXTORCH. It's compatible with the company's T6A, as well as SUREFIRE 6P, 9P, G2, G3, and other xenon models. From off, twisting to tighten activates solid green light, and twisting again after turning it off activates green flashing. The flashing cycle is about 0.8-0.9 seconds. Tightening further will only activate the main xenon bulb. *It does not function correctly with P60 LED modules.* It may flash rapidly, fail to light, or light simultaneously. By the way, when attached to a FURY, it lights dimly as shown in images 13-16. While it makes the location of the light visible during power outages or at night, it consumes power unless the tail is loosened to turn it off, so caution is advised. All lighting images are for reference only. The item for sale is the tail cap only. It is a new, stored item, but it has been opened and tested. Please refrain from purchasing if you are sensitive or particular about details. No pets. Non-smoking environment. Ships via Yu-Packet Post or Post Mini.