For the design of the Piet Boon by COCOON bathtubs, shapes have clear functionality and powerful volumes. The shape of the bathtubs may be described as a rounded rectangle enhanced by an ergonomic organic shape on the inside. A double edge on the marble version ensures that the solid wood accessory shelf may be inserted precisely. The shelf rests on the inner edge of the tub and runs parallel to the highest outer edge of the tub. The bath made of durable solid surface contains not a double but a single edge, so that the shelf rests on the bath edge. A deliberate choice was made to increase the size of the tubs, resulting in a very spacious and comfortable bathtub. The wide surfaces accentuate the properties of the outside of the bath, both in the solid natural stone variant and those made of a durable and solid surface.