BD's latest incarnation - the ATC GUIDE combines auto-blocking capabilities with traditional harness mounted belay function. This allows one device to be carried and used for multiple purposes: belaying the leader, auto-block belaying of one or two followers, lowering, and high or low friction rappelling. Handy too, is the second clip in point - which allows your ATC-G to be rigged for conventional belaying while the device is still clipped to your harness, reducing the chance of fumbling and dropping it. To use in auto-block mode you must have a strong and redundant anchor master point which the ATC-G's large carabiner hole can be clipped to. Ropes are threaded and clipped with a locker - the same way you would rig for belaying a lead climber - with the tail ends exiting the grooved side. If your second slips, his weight bears onto the rope and ATC-G - not you... making for a comfortable and easy to control belay. Assorted colors. Use on 7.7-10.5 mm ropes. Instructions included.