In series to the DC supply to a Yamaha P120 piano , 0.1 ohm or less even warming with a soldering iron, so not a thermistor. It is yellow epoxy cased and about 8mm sqare like a plate capacitor marked HFBA CHINA UF250 or UF25C with logo of V superimposed over an upturned V and then 3e
I assume its a working order fuse , but value 2.5 amps ? The supply is rated 16V, 2.4A
-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on
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