Harbor Freight Quantum 18650 flashlight adapter

thingiverse

This is an adapter for the "Quantum" brand LED flashlight sold at Harbor Freight, specifically the SKU 63934 model that runs on four AAA batteries and lasts a mere twenty minutes. It's likely to work with other flashlights featuring a plastic tray holding four AAA batteries. Printing this adapter takes approximately thirty minutes, so feel free to give it a try. To complete the circuit, you'll need to create a conductive bridge between the tailcap and the body using aluminum foil or opt for a more advanced solution like printing in conductive filament. Interestingly, this flashlight is incredibly bright when powered by a single 18650 battery, and I'm confident that its runtime will exceed twenty minutes.