Wall Nuts

I keep all sizes of these connectors in my electrical tool box.  They are very handy when you need to connect multiple wires and have limited space.  They come in a variety of configurations for different size wires and different wire counts.

There are a number of different styles. If you think you will be removing the wires, you might want to purchase the ones with a small lever to remove the wire. Otherwise, you will need to twist the wire back and forth and work it out of the socket.