This is a adapter kit for the MKIII wind turbine by 3dprintable1 ( https://www.thingiverse.com/thing:2851306 )  designed for german HT DN50 pipes. The original kit makes use of standard UK drain pipes with an inner diameter of 64.50mm which are not available in germany. The top adapter is designed to snuggly fit over the pipe connector top ("muffe" in german). The bottom part has a really tight fit and requires some force and stomping to get onto the pipe