I noticed that my extruder motor was very hot after a very complex print that required a lot of retracts. After some research and looking for the best value for money (multiple heatsinks so I have extra room for future problems with other stepper motors) I settled on this product. After installing these heatsinks on the bottom of the extruder motor on all three of my printers (Ender 3 Pro, Ender 3 V2, and Longer LK1), I immediately noticed a temperature drop and my extruders aren't getting as hot as they seem. They must not be touched after making complex prints that require a large number of touches.