42-28mm Copper Press Fitting Reducer is to reduce 42mm fittings to 28mm. The Geberit Mapress Copper fittings are easy to press, giving you a quick and reliable install without soldering. For crimping use a 28mm M profile jaw. More info and resources Everybody wants a leak-free job. So to make sure you follow the correct system installation procedures, head over to our specialist Hybrid Hub. You'll find loads of technical and training resources, plus pretty much everything you need to know about Hybrid and Pressfit: www.pressfitsolutions.com