This harness states it will work for rats and ferrets. The larger part of the harness was velcro and didn't even fit my rat's belly (I guess he's kind of chubby), but the smaller "neck" part of the harness was too big and was not very adjustable. He slipped right out and could undo the velro no problem. I am still on the hunt for a good rat harness, because my little guy would probably love some time outdoors. I may have to breakdown and make one myself because good rat-specific products are hard to find.

Pros: Seems fairly durable

Cons: Does not work for rats, as advertised

Walk-N-Vest comes in a variety of colors and sizes to suit your pet rat, or your pet rabbit! These vests are made of a stretchy mesh material that allows their skin to breathe as well as prevents irritation, unlike those cord harnesses. They also feature velcro for smaller animals and snaps for larger animals for easy adjustment and a comfortable fit. These vests also come with a finder bell and a stretchy leash to accomodate you and your pets curiosity.

Pros: Comfortable to wear

Cons: -

My fiance and I use these on our two ferrets and they work absolutely great for us. The only thing that sucks is trying to put them on our girls while they're squirming around.

Pros: They stretch to fit

Cons: It can be difficult to find the correct size since they stretch