1、 Made of heat-resistant and non-stick silica gel material, which can resist the accumulated molten plastics and withstand high temperature of 280℃. 2、 Help keep the stable hot-end temperature, especially when high airflow cooling is used around the nozzle to cool the print. 3、 By keeping the heater block and extruder clean, the service life of the heater can be extended while retaining the heat inside the hot end and keeping it out of print. 4、 Professional for 3D printer extruder, heater aluminum block silicone protective cover, suitable for MK7 MK8 MK9. 5、 Usage: push the cover plate to the front of the hot end without removing it - they will fit tightly when first cooled, and the silicone will expand to the correct size to fit the hot end.