The Petzl Grigri features a self-braking function that helps the belayer catch and hold a climber, making it great for working routes. Works equally well for lead climbing and toproping. Ergonomic design makes for smooth, controllable lowers. Also great for rappelling on single ropes & perfect for setting and cleaning routes. Features: Self-braking system: if the rope suddenly comes under tension (e.g. in a fall), the cam pivots to pinch the rope, thus helping the belayer stop the climber's fall Usage is similar to that of conventional belay devices giving/taking slack is done by using both hands to slide the rope through the device Falls are held by holding the free end of the rope with the brake hand for lowering and rappelling, the rate of descent is controlled by the hand holding the free end of the rope (the rope is released with the handle) Specs: CE Certified Aluminum side plates Stainless steel cam and friction plate Reinforced nylon lever arm For use with a single 10-11 mm UIAA dynamic rope (9.7 accepted) Weight: 225 grams American Alpine Institute's Guideschoice