The ultra-light, keylock Ultra O carabiners are the mainstay of the carabiner market, and for good reason. Not only do they give high strength to weight ratios and feel great in the hand, they also help to keep components of a system aligned. The deep symmetrical basket allows pulleys, webbing, ropes and even other carabiners naturally sit centrally in the oval basket but still allow easy stacking of components on either side. Any weight transfer then happens without any unnerving jumps associated with offset and D shaped carabiners. The Locksafe model is a perfect companion to the DMM Buddy and excels in technical "Working at Height" applications especially rope access and arbor.