Designed to fit 3-hole weir boxes to create an 80-20 'sipping' configuration. Comes with 4 rigid pipes, (including one with a valve fitted) and return pipe work parts. This pipe work kit is intended to handle a maximum of 3000 l/h. For guidance, with marine it is recommended that one kit is used per 300 litres and freshwater one kit per 600 litre capacity aquariums. Specifications: 26mm diameter pipes, 36mm diameter holes required to install. A length of 20mm flexible pipe will be required to connect to return pump (not included). Not compatible with our solvent-weld range of pipe