this is the first time I see such a buoy. It is an all in one! there are the jackets and the buoy of the abdomen, the assembled everything. This does not swell, it's a little hard foam. The fabric looks like gabardine. I'll bring you a picture if your "mistourinette" is not too plump, the buoy can be used until 4/5 years. Maximum weight: 30 kg
I highly recommend this system because we can never be too careful ...