This part is a kind of semiconductor called NTC10D-20.

Function of this product has NTC THERMISTOR.

Manufacturers : ETC

Image and pinout :

Some of the text within the PDF file :

NTC NTC THERMISTOR NTC NTC THERMISTOR OUTLINE 2 1200 4 This is a Negative Temperature Coefficient Resistor Whose resistance changes with ambient temperature changes. Thermistor comprises 2or 4 kinds of metal oxides of iron, nickel,cobalt, manganese and copper, being shaped and Sintered at high temperature(1200 to 1500 ) 1500 NTC Rt Critical Technical Parameters of NTC Thermistor Rt---Resistance Value at Zero-power It's a resistance which is got at a fixed temperature on a basis of a testing power which causes resistance to Vary in a range which can be ignored in relation to the total testing eror. R25 R25---Resistance Value at Rated Zero-power The design resistance of the thermistor usually refers to the resistance value got at Zero-power at 25 , which is usually indicated on the thermi [ ... ]

NTC10D-20 PDF Datasheet Download