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Budget watch/tools demagnetiser modified by incorporating thermal protection. There are discussions within a watch enthusiasts, whether is a safe and/or necessary to use demagnetiser on quartz movement. I leave this question out of this topic, which aims bringing an awareness of lacking tool’s thermal protection and providing solution. SEIKO memo about magnetic influence Credit to TheHWcave for the research, test and trial on the YouTube link below. Thermal protection based on a PTC (Positive Thermistor Coefficient), the power lead is moved to the opposite side to ensure that nothing is near the PTC as it generates heat (+130 C) when current flows through by increasing its resistance, and I also perforated the back cover to improve cooling. The maximum current of the demagnetiser is around 200mA. The following thermistors were considered and I opted for B755, mainly due to its availability. Note, during operation, the thermistor's surface temperature can be very high. Ensure that adjacent components are placed at a sufficient distance from the thermistor to allow for proper cooling. Datasheet https://www.tdk-electronics.tdk.com/inf/55/db/PTC/PTC_ICL_OC_Leaded_260V_1000V.pdf PTCCL05H390HBE VISHAY, PTCCL05H390HTE Datasheet https://www.vishay.com/docs/29087/ptccl265vseries.pdf The video instruction is available here The demagnetiser is bought on Aliexpress, costed less than €10 https://a.aliexpress.com/_EwvnkUV PTC B755 5pcs €10 https://www.ebay.ie/itm/35581758210...h2gJ7fPRBW&var=&widget_ver=artemis&media=COPY