A revolutionary new way to open jars. Innovative Swiss engineering tightens this tool"s jaws around the cap, even as the jar is being opened, so the opener never slips. The Kuhn Rikon Gripper stays locked on lids and doesn"t let go. Place The Gripper over jar lid, rotate turn-knob clockwise to tighten jaws onto lid. Tool locks in place. While holding the jar or bottle securely, grasp the handle and push counter-clockwise to open. Just loosen turn-know to release lid. The Gripper opens threaded caps and lids from 1-inch to 3.5-inches. Works on smooth-sided and grooved caps, too.