The only automatically locking belay device which: Has a completely panic-proof locking mechanism. The REVO has no method of over-riding the locking mechanism, during belaying, or when lowering a climber. Is bi-directional, the locking function works regardless of the rope direction. Has an intuitive belaying method, which requires no changes to standard belaying technique. Has no need for a specific locking karabiner. All of these USP's contribute to make the REVO the safest belay device available.