The Pet One Critter Roller is the perfect accessory for your pet mouse or rat. The well ventilated, clear plastic round roller allows your pet to get a view of their surroundings in the safety of the Critter Roller, all whilst keeping active! Always supervise your pet’s playtime, and be sure to keep them in a shady and safe spot when exercising. Once you feel they have had plenty of fun, return them to their home and be sure to have plenty of clean water available.