Niteangel Super-Silent Hamster Exercise Wheels: - Quiet Spinner Hamster Running Wheels with Adjustable Stand for Hamsters Gerbils Mice Or other Small animals> Why we designed Niteangel Super Silent Series Hamster Exercise Wheel? As all known, wild hamster runs about 8-miles at night, a reasonable hamster wheel design means lots of running fun & exercise chance for a family hamster, it also benefits for their physical & mental well-being at the same time We studied kinds of hamster wheels and noticed most of the hamsters' owners care about the safety & noise of the hamster wheels. We tried & designed many times, find out and fix the problem again & again, finally, we achieved this Niteangel Super Silent Series Hamster Exercise Hamster What're the special designs of Niteangel Super Silent Series Hamster Exercise Hamster? <1>. Dual-Ball bearing Design - Helped to reduce the squeaking sound due to high rotating, also less the wave of running drum when hamster running, more stable & soundless. Brings your a super silent sleeping time, no matter your hamster's cage at other places or in your room <2>. Reasonable Size - Due to different sizes of Dwarf hamsters and Syrian hamsters, we devised 2 sizes separately for them A. 8-inch Inner Diameter Hamster Wheel with the 3-inch wide running track, which fits for most of the dwarf hamsters, small mice, gerbils, or similar sized pets, except the largest dwarf hamster B. 10-inch Inner Diameter Hamster Wheel with the 3.7-inch wide running track, which fits for most of the Syrian Hamsters, mice, gerbils, rats, degus or similar sized pet, except the largest Syrian hamster <3>. Comfort Hamster Wheel - Reasonable Size of Running Drum & Wide Running track brings a relax back feeling, as they do not need to bend their back when running, let them enjoy their endless running time, help them to build own muscle, keep them happy & mental well-being