Super Pet Clear Run-About Balls provide pets and pet owners with interactive fun during playtime. Sized perfectly for hamsters and gerbils the 7 inch Clear Run-About Ball provides the ideal outlet for your pet’s excess energy. Durable plastic construction with lock tight lid for safety. Clear Run-About Balls also make a great temporary holding area to keep your furry friend while you are cleaning their cage. For added safety use your Run-About Ball on Super Pet’s Hamtrac Raceway and provide your pet with a controlled exercise environment.