This Kuhn Rikon jar opener tightens its jaws around the cap and won't let go until the lid is off. Place the opener over the lid and turn the church key knob clockwise to lock it in place. Simply hold the jar, grab the handle and press counter-clockwise to loosen and release the lid. Open smooth-sided, grooved or threaded caps, including vacuum-sealed caps, from 1" to 3 1/2" Dia. ABS plastic. Stainless-steel teeth and handle. Dishwasher-safe.