Trapped Shower Gullies (TSGs) are designed to create a wet floor area and not to fit into traditional shower trays that have a 52mm or 90mm diameter waste hole. However, there are a number of floor formers that contain a larger waste hole with the required falls that may be able to accommodate a McAlpine Trapped Shower Gully. You should check the dimensions with the floor former manufacturer to understand if the McAlpine TSGs will be compatible with their products.