When you're building your own custom electronics projects, a simple power switch isn't always easy to find. If you have some DIY projects that use 9V batteries, this super-small power switch is fairly easy to build and is mostly made from an old 9V battery.
Sean Michael Ragan at Make wanted an easy way to turn off his own projects without having to disconnect the whole battery. He couldn't find a 9V power switch to buy, so he made one himself.
To make your own, you'll need to know how to solder, and you'll have to get your hands on a small slide switch and some wires. Beyond that, the rest of the build is comprised of pieces from an old 9V battery. Once you have it all put together and tested, you can clip in a 9V battery and switch it on and off easily. For the complete instructions, check out the link below.