The AVIATOR Pet Bird Harness and Leash X-Small Black Aviator Harness for birds weighing between 110 - 190 grams or 3.9 - 6.7 oz: Medium to large quaker parrots, caiques, senegals, average sized doves, medium-sized parakeets (Indian ringneck, Port Lincoln), rainbow lories, rosellas, noble macaws, large conures (sun conures, jendays, nandays, blue crowns), Indian Ringnecks; Hahn's Macaws ESCAPE-PROOF! With other brands of harnesses, your bird can easily remove the leash and harness. The Aviator Harness keeps your pet safe and secure. Self-adjusting leash: Automatically adjusts from the chest to the back as the bird climbs and flies. Fewer pressure contact points on bird. The strong steel slides have been powder-coated black to make them unattractive as toys. However, we have not heard of any bird yet that was able to break it. Easiest to install - one piece design - No buckles or clips.