Freestanding bathtub in solid surface RIHO. The design freestanding bathtub combines simplicity and quality, Matt white solid surface bathtub (inside and outside). wide range of colours for the exterior side of solid surface bathtubs, the interior side always remains in matt white. This oval-shaped tub has an overflow that prevents water from overflowing. With its eccentric central waste and its double back, this bathtub is very comfortable. The designer freestanding bathtub is easy to install and maintain. RIHO makes a contribution to modern bath culture. It is a European brand of international level. The wide range of bathtubs we offer is produced entirely in-house in our factories in Europe. Solid Surface refers to a family of rather high-end materials, made from a mixture of natural materials (bauxite), acrylic or polyester resins, and pigments. The solid surface is sturdy like steel. invisible joint after sanding. easy to maintain because it is homogeneous and non-porous: very resistant to stains and humidity, and repels most bacteria. thermoformable.