Avi One Mineral with Plastic Links are designed to provide enrichment and entertainment for your feathered friend. Providing environmental enrichment for your pet bird enhances their quality of life, instincts and overall health and wellbeing. Simply hang on the cage and let your bird enjoy. Approx Dimensions Small 12.5cm (Small Birds)Medium 15.5cm (Medium Birds)Large 16cm (Medium Birds) Recommended For Small Birds - Parrotlets, Budgerigars, Kakariki, Plum Heads, Cockatiels, Lovebirds, Small Conures (Green Cheek, Brown Throat) and similar sized birds. Medium Birds - Quakers, Senegals, Indian Ringnecks, Port Lincoln, Rainbow Lories, Rosellas, Noble Macaw, Hahns Macaw, Medium Conures (Sun, Janday, Nanday, Blue Crown), Caiques, Pionus and similar sized birds.