What a wonderful, all natural, refillable, large all wood bird toy for very destructive beaks. Especially those that chew rope! This toy is completely made of chain. It weighs close to five pounds and has a nice combination of hardwood wheels, 1" pine rectangles, and all natural wood slices. Each of the four strands has a solid, bird safe welded O ring at the bottom. At the top of each strand are four quick links connected to hooks. These will come very tight so your bird cannot open them. When it comes time to refill the toy, open the quick links with pliers, refill the strands and put them back on! Instantly you have a nice new toy. The center block of wood that everything hangs from is a very hard piece of maple, and I have yet to see a bird that can do much, if any damage to it!