The IDEAL Wire-Nut® Wire Connector set new standards for innovation, quality and convenience when it was first introduced in 1928. As the first screw-on wire connector in America, it literally set the industry standard for years to come. With a fixed, square-wire spring and a positive grip shell, the Wire-Nut® is perfect to twist-on with fingers for a secure connection that will last. The refined wire range makes it the best choice for fine stranded wire applications. The Wire-Nut® also features a tough, flame-retardant thermoplastic shell that withstands environmental extremes and is reusable for easy circuit changes and addition. With five color-coded models available, Wire-Nut® Wire Connectors will handle any job from as small as #22 gauge wire up to #6 gauge wire.