After seeing many unsafe, poorly executed versions of these circulating, we researched, tested and sourced the safest products to use. This kits will include a roomy "pit" and a variety of balls, including some of our Treat-E-Balls. It will fit in both the Start-R and I-Home cages. These "Ball Pits" can be enjoyed a variety of ways; one example is a few Treat-E-Balls stuffed with a treat or food and buried in the pit for foraging. This colorful, interactive toy will provide hours of fun for your pets! Easy to clean and Glider Safe!