The Wing-Nut Wire Connector provides an easy, secure grip when connecting a wide range of wires. The specially designed contoured wings make for extra torque and quick work on any electrical job. The wide range, live-action spring is flexible enough to handle small combinations with ease but then expands to accept large combinations when you need it. It can also be reused on same size or larger combinations for quick and easy circuit changes and additions. The Wing-Nut also features a tough, copolymer, flame-retardant shell that withstands environmental extremes with a deep skirt that provides maximum dielectric protection to prevent flash-over and turned-back strands."