our store Self locking on pipes and nuts (view larger). No more time-consuming test-adjusting to achieve the correct size. With the Knipex Cobra water pump pliers, you can simply position the upper jaw to the workpiece, push the button, and close the lower jaw. And you'll also be able to say goodbye to blood blisters you get with other gripping pliers. With safety its first priority, Knipex has designed a built-in pinch guard that prevents blood blisters on your hand. The unique self-locking adjustment and induction hardened gripping teeth means that once it's set, it stays. There's no slipping and no need to waste strength squeezing the pliers — ensuring operator safety and more efficient work. Cobra's unique jaw configuration can grip any shape object — flat, round, hex, or square. It also eliminates nut burring to avoid stripping pipes, nuts, or bolts. Additionally, the Cobra's newly redesigned adjustment provides 30 percent more gripping capacity than previous models. A simple push of the patented push button adjustment maintains jaw size setting and gives you the correct size opening every time.