3x D Cell to 2x 18650 Adaptor

thingiverse

A handy print job that lets you swap out devices powered by D Cell batteries - those old-school powerhouses nobody uses anymore. It's easy to modify these devices to use 1 or even 2 high-performance 18650 cells instead. This battery sleeve is simple in design, measuring the same length as three standard D cells. Inside, there's a hollow space that can accommodate up to two 18650 cells and a convenient slot for wiring. I used it to upgrade my 1W LED flashlight from D Cell batteries to 18650s - a great mod that worked like a charm! I'm sure you'll find even more creative ways to use this versatile battery sleeve.