The idea of a soap box for floating soaps comes from the fact that after showering, a wet soap will stick in the soap box. If you take this soap out of the soap box later, a valuable soap residue remains on the bottom of the box.
Thus, we have developed a soap box that is smooth on the inside to receive our soap holder with suction cup on the bottom. The soap holder can be removed from the shower wall and installed in the soap box. The soap is then placed onto the soap holder.
The soap will be floating in the closed soap box and can completely dry.