Assortment of small animal habitat pieces with exercise balls by crittertrail.  There are 2 small exercise balls and 1 larger one. The smaller ones are perfect for dwarf hamsters. That is what I used them for. The large clear ball is good for gerbils and regular hamster, rats, and etc. There are two bottoms, two tops, and surrounding wire for the houses. I don't have the side panels. 2 outside exercise wheels that normally clip onto the ends. Great for replacement parts. Condition is "Used".