The Petzl Grigri Belay Device's self-locking system has made it a staple item at sport crags from Smith to Rifle to the Ceuse. Its internal cam locks when a sharp pull occurs to help you catch your partner's monster whipper when he skips one clip and botches the next. It also makes it much more comfortable to hold tension while he hangs and works out the moves. Aid climbers love the Grigri for belaying long A4 leads. The Petzl Grigri Belay Device's lever releases the cam to allow smooth lower. *Rated for ropes from 10 to11mm.
Bottom Line: The Petzl Grigri Belay Device represents the sport climbing standard.