Polypipe PVC Underground Drain Back Inlet Bottle Gully 110mm is used to prevent any foul smelling air escaping from the system and features a back inlet for 110mm pipes. It can be used to accept water from kitchens, ground floor bathrooms and similar waste areas. It has a polypropylene grid to prevent debris from entering the gully and acts as a rodding point for cleaning. It is an alternative to traditional clay drainage systems and features a simple seal and snap cap system for strong and durable joints.