Profiled manhole base composed of an injection-moulded manhole body, equipped with reinforcing ribs, steps and a flow profile adapted to the outlet diameter. Suitable for connection to standard pipes of type PVC-U, PP and PE. The connections are fitted with fixed lip seals. The manhole body is equipped at the top with a riser collar with lip seal for watertight connection of a ribbed PP DN400 riser pipe. Maximum installation depth: 6 m Permissible groundwater level: 5 m Traffic load: SLW60