This part is a kind of semiconductor called CP431.
Function of this product has Adjustable Precision Shunt Regulator.
Manufacturers : Ceramate Technical
Image and pinout :

Some of the text within the PDF file :
CP431 Adjustable Precision shunt Regulator ! •$ ! CP" !CP" / 6 7 "&'(8(9 3( 7 + / + 7 : 8;!/9 ) $" !" + [ ... ]
CP431 PDF Datasheet Download
