AA to C Battery Adapter

thingiverse

People are getting fed up with the high cost of larger batteries, such as C, D, and 9-volt. That's why I decided to create a simple battery adapter that anyone can use. All you need to do is insert a fresh or slightly worn AA battery into the center of this adapter, then drop the entire assembly into whatever device requires a C battery. Most standard AA batteries will fit snugly at the bottom of the adapter, preventing them from falling out as you try to install the new C battery in your device. There's also a convenient label on the side of the adapter that says 'AA to C Adapter' - just in case you forget what it's for.