I bought the speedy fit water but diverter kit because I have a cast iron downpipe that I didn’t want to slice in two to fit a standard diverter. Irritatingly the cast iron downpipe is good old 2 1/2” British pipe, not the minimum 70mm recommended for this product. I had a good chat with the customer service technical team who explained what pipe sizes they had already fitted it to. I think they said they might have done 60mm plastic, but they advised me that it would not fit 50mm pipe. Armed with this knowledge I went ahead and bought one. I’m please to say it does fit, and hopefully when it next rains in about 6 months time (!!) I’ll see how well it works. The fitting process is simple, the tank cutter is a good tool, however you need a powerful, high torque drill (I used a Bosch Advanced Impact 900) to cut into the pipe - you also need patience and some pretty strong muscles. It took me over two hours to finally cut the hole out of the downpipe. Worth it now it’s done. It looks smart.