The special composite blade provides excellent thrust never before experienced with children’s fins. The fin strap is specially designed so children can put them on. (if a shorter adult grade fin strap was used – there would be no “give”and the strap would not be stretchable, therefore impossible to put on.) Our strap is designed narrower and with a more flexible rubber and finger tabs that is stretchable yet durable. The result: Joe’s Squidz Rocket is the best value open-heeled fin you can get for your young child.