This is a Adaptive Tactical known as the EX Performance, model AT-02901.
The Adaptive Tactical EX Performance Tactical Light Forend for Mossberg 500 & 88*" 590 series 12g pump shotguns is a compact and powerful 300-lumen tactical flashlight that seamlessly integrates into the forend body. Three levels of illumination are designed to offer wide" smooth beams ideal for close-range" shotgun applications. Removable light reveals a 2 inch picatinny rail for attaching other accessories" or rail may be concealed under the included nose cap.
Features:
300-lumen beam features a run time of up to 3 hours
Powered by 2 AA batteries (included)
3 settings: Momentary On Constant On Rapid Strobe