Penn-Plax offers its Bird Life Natural Weave Kabobs. They are designed to provide stimulation and are available in three sizes ranging from 12 in. up to 24 in., making them appropriate for a wide range of popular birds, according to the manufacturer. They are constructed of natural materials and are ideal for climbing, the company states. Each toy features a safety clasp for attaching to the bird's cage or playpen, and the Kabob can be stuffed with nesting material to keep birds busy and stimulated, according to the manufacturer.