I bought 2 for boxer puppies, they fit us up to 6 months, in the smallest body they can also fit us up to 7 months I believe

Excellent Quality-Price Ratio. Very Durable for my Dog who has a lot of "Nerve" and pulls a lot! Because I struggled a bit at the beginning because I couldn't find installation instructions, I provide a mini guide: It has a relative difficulty in placement and more specifically during initial adjustment. We need to adjust one strap to fit properly around the dog's neck like a collar and the second one to buckle around his body, so essentially it is placed with 2 "clicks". It does not have the convenience of being worn immediately by passing under the dog's legs. However, the 2 independent buckles make it particularly sturdy and the built-in handle on the top helps control the dog in unexpected situations. It is ideal for everyday walks with the dog with a folding leash, but a bit cumbersome (due to the 2 buckles) for urgent "need". So it is good to also have a simple collar with a chain for immediate use and convenience. Personally, I wear it on my dog all day because it doesn't bother him at all, neither during movement nor during sleep, and I take it off after the last walk of the day.