Habit rail OVO Maze Cardboard Insert Value 6 Pack provides 6 times the fun with 6 interactive chewable cardboard Maze Inserts that are designed to fit various Habit rail Habitats or Add-ons, with pre-cut slots to hold the food or treats in place. The chewable Tree House, Beach Scene and Doll House are designed to provide hamsters with hours of foraging fun, gnawing away at the maze in search of food or treats. The maze helps satisfy your hamsters natural chewing instinct, while providing exercise and helping to alleviate boredom.