Bathroom Furniture and Sanitary Ware Design Serel Luvi Urinal Set Self-Cleaning by SEREL Ceramic Factory Primary purpose of Serel Luvi Urinal is to deliver maximum hygiene. SEREL designed a product compliant with this purpose both in terms of the surface technology that is used and the form of the urinal. No detail was used that would complicate cleaning in urinal. In the urinal, water flows with a free flow discipline from a horizontal line created in reservoir. Encountering positive relief placed just below the horizontal line, water can easily clean the entire reservoir with guidance of relief.