LilyPad Simple Power
The LilyPad Simple Power is a board that lets you connect a battery (or other power source) and switch it on or off, that's it! We provide you with a JST connector and a slide switch. You can solder in your own surface mount (or through-hole) resistor in line with the output, or solder the jumper closed if you don't require a resistor.
LilyPad is a wearable e-textile technology developed by Leah Buechley and cooperatively designed by Leah and SparkFun. Each LilyPad was creatively designed to have large connecting pads to allow them to be sewn into clothing. Various input, output, power, and sensor boards are available. They're even washable!