Pet Exercise Wheel, Pet Wheel for Sugar Gliders, Rats--Stealth Wheel; Blue XMount by Atticworx Semi-closed front so your pets feel secure. Crossbar free to protect tails and little feet. Heavy duty and trouble free "Stealth Quiet Hub" featuring a sealed ball bearing and housing. 5 inch wide running surface is made of durable black plastic mesh with 1/4 inch holes. Mounts right to side of cage with zip ties (included).