The Magnum Monsterjax represents the next level of innovation for limb dampeners, they really reduce noise and vibration! They come with thick rubber pads that go in between the limbs. Utilizes screw to affix into place. Minimum of a couple feet per second speed loss. Easily install with provided screws. These fit 11/16" width gap. Fits new Bowtech, Hoyt, New Breed Bows, and Parker Crossbows.