This is a 3D printed pistol grip with a trigger switch that fits ~1" diameter flashlights made by Convoy (L21B, M21B, C8+, S16, ETC). It uses the Convoy remote switch (for L21B, for M21B, for DIY in almost any Convoy light with a tailswitch) to allow the user to control the flashlight using the trigger on the pistol grip.
There are two STL files: the trigger and half the grip. Copy & Mirror the grip half in your slicer to get both halves. Print with 0.2mm layer height, 10% infill, and supports. Use short lengths of filament for the trigger hinge and locator pegs.
The author hasn't provided the model origin yet.