Here is a review left by a customer on a product. Would you say he was satisfied or dissatisfied?
Title: Don't expect it to stay on a rat.
Review: Though the packaging depicts a rat fitting snugly in this small-sized version of the comfort harness, even the largest and fattest of my four rats managed to deftly wriggle her way out of it in a matter of minutes. This item might be suitable for an exceptionally large male rat, but be aware that for your typical, adult, well-fed fancy rat, it will prove essentially useless.
