INTERJOLLY optimizes the corner joining of the tile covering between floor and wall, while leaving the necessary space for the expansion with adjacent walls. This profile has a perforated flange which is applied under the tile. It can also serve as a cove base for shower tray and bathtub perimeter so to avoid the silicon lining which inevitably turns a yellow unaesthetic discoloured tone in time. The moulded cove base made with the application of the profile makes every internal corner and crevice extremely easy to clean and therefore more hygienic.