This key allows you to screw your nozzle as close as possible to the Heatbreak to protect your extrusion block from filament leaks. It is important to note that using this key is necessary for optimal tightening, as hand tightening, even very firmly, is not enough!
This key is equipped with 4 tips of 7 mm, 5.5 mm, 4.8 mm, and 3.8 mm, making it perfectly suited for M2, M2.5, M3, and M4 screw nuts.