We all know that rappelling is the most dangerous part of climbing. With Beal's Jammy Prusik you don't have to leave anything to chance. Beal created the Jammy with the fear of botched knots and your safety in mind. Constructed from rope with a nylon sheath and aramid core this sling weighs just under an ounce but adds an extra element of safety to your climbing day. The Jammy's recommended prusik knot is a Machard but this sling can also be used to create a speedy rope clamp for swift hauling. The rope's material resists heat and damage from friction and is supple enough to grip thinner rap ropes. While the Jammy's purpose is to up the safety for rappelling or hauling this sling would not be a wise device to whip on or weight with gear.