Foam life jackets such as the model KADEMATIC® 10 F have several advantages. They provide buoyancy at any time and are almost service-free because they have no mechanical components. Furthermore they can hardly suffer any damage.
On the contracry: since they are made of foam material they can take many a poke. That is why they are most suitable for children who want be carefree, play, and experience their adventures by protected waterbodies.
But careful: foam life jackets are not safe for unconscious persons, and in terms of performance they fall short of automatic models.