Slip the wire into the self locking collar, and stretch with a come-along, power-pull or any other stretching device. Wire will not slip no matter how hard you pull, actually the harder you pull, the tighter the wire grip grips. The heavy durability and simplicity of design make this item an all time best seller. Heavy Steel Construction. Easily grips Barbed wire, smooth wire, and small cable. Attaches to most common stretching devices. Small enough to carry anywhere. 5 inches long, 14 oz.