From Floplast
This Floplast 110mm Universal Rainwater Adaptor is a rubber adaptor which enables you to install a rainwater downpipe either square or round into a 110mm drainage pipe. Key Features: Manufactured from rubber Accepts 65mm square and 68, round rainwater downpipes Light weight and easy to install Fits FloPlast 110mm pipe or drain fittings No glue or mastic required