This 4-button keyfob remote goes with Adafruit's basic 315MHz RF receiver modules. It will work with all of them, sending out one of four commands that match up with the four outputs. Its small and light weight and will work up to 25 feet away depending on line-of-sight and obstructions. Since this is just a transmitter, if you have multiple receivers, it will turn all of them on and off at the same time (there is no sub-addressing)
A matching RF receiver is not included, you'll need to purchase one in addition!
Uses two CR2016 coin cells, not included.