Hoppers are used to bring together a collection of flows into one downpipe. Usually this would be different rainwater pipes from various sections of a roof coming together, such as pipes from a main roof and a porch roof.The hopper is essentially an open box into which the upper pipes discharge. The lower section of the hopper connects to a 68mm round or 65mm square downpipe.On occasion if there is a combined system of drainage on much older properties, hoppers are used to feed waste pipes from a bathroom into a rainwater downpipe. As combined drainage systems are no longer in use for new properties this is a much less common use for a hopper.Our PBSL Group short video introduction for this product can be viewed below;