I was dissatisfied with the freely available coolers for my applications and so decided to design my own version. The most important feature for me was the use of a 60 mm axial fan to be able to guarantee a high volume flow and thus excellent cooling performance. This is crucial when using high-temperature filaments (e.g. nylon) and at high installation temperatures (e.g. ASA > 60 °C). Hotend cooling is required to restrict extrusion to the heater and nozzle. Without sufficient cooling, the heat will rise and cause clogging. I optimized the cooler for the MicroSwiss Hotend at my Creality Ender 3 Pro.