Gardner Bender 10-089 WingGard Twist-On Wire Connectors, 14-6 AWG, Electrical Wire Nut, 50 pk, Blue DESIGNED TO LAST: Wings are knurled for a sure grip and offset from centerline for greater twisting leverage. Square wire spring grabs and holds wires for secure connections. DESIGNED TO LAST: Square-wire zinc-plated spring instantly adjusts to the shape and size of the splice FLAME-RETARDANT TEMPERATURE RATING: Flame-retardant properties resist heat distortion up to 105C / 221F HIGH-DIELECTRIC: shell features deep skirt design to prevent exposure of bare wire - COPPER TO COPPER connections only STANDARD RATING: 600V max in building wire and at 1000V max in lighting, fixtures/luminaries and signs UL LISTED: Canadian and U.S. requirements (connections rated at 600V Max for building wiring and rated at 1000V Max in lighting fixtures/luminaries and signs) WIRE RANGE: 1 #10 with 1 #12 (Min) to 1 #8 Str with #8 Str (Max) Unsurpassed quality and durability in a high-leverage, easy-on wing-type design Easy-on, easy-off without tools Expandable square-wire spring instantly adjusts to the shape and size of the splice, then bites down to thread onto the wires without ratcheting and creates a strong, vibration-resistant connection No pre-twisting or tools are necessary Tough thermoplastic shell shields against environmental extremes