I found the following in a discription for wheels on an online site:
>>It's the "Sensational Safety Wheel for Small Animals!" The Giant
>>Comfort Wheel features a safe, solid running surface, whisper quiet
>>operation, a "tail safe" design and versitile. Can be attached to your
>>pet's cage or can be used free standing with the included base. For
>>pet rats, chinchillas, and guinea pigs.
I then emailed their customer service office, and they replied:
Hi Andrea,
Thank you for your comments about the wheels. I was unaware that you
could not offer a wheel to a guinea pig. This type of information is
never overlooked and we appreciate that you took the time to advise us
of this fact. I have forwarded your email concerns to our management
staff for review.
Best Regards
-I hope their email isn't just blowing me off...although I feel like it is.