Flexible couplings incorporate a rubber body with stainless bands to enable the fitting to compress down onto different sizes and types of pipe.One end of this stepped adaptor can be connected to a pipe with an outside diameter of between 108mm and 122mm, whilst the other end connects to a pipe with a diameter of between 121mm and 137mm.Ideal for joining PVC drainage pipe to other drainage materials such as clay, salt glaze, supersleve, asbestos cement and pitch fibre.There are many types of drainage materials that are still in use from previous generations, and connecting on to them can sometimes prove problematic. Flexible couplings remove the need for a multitude of different size adaptors by their adjustable nature.As the steel band is tightened (like a jubilee clip), the EDPM material from which the coupler is made compressed uniformly around the pipe, forming an airtight and watertight seal. The clips are made from stainless steel which means that they are impervious to rust.The steel bands are adjusted and tightened using a screwdriver.Not sure how to use it? Click here to watch a short video.