This part is a kind of semiconductor called AZ41.
Function of this product has Full Wave Rectifying Valve.
Manufacturers : Philips
Image and pinout :

Some of the text within the PDF file :
page 1 2 3 AZ41 sheet 1 A FP date 1953.06.06 1953.06.06 1999.06.26 [ ... ]
AZ41 PDF Datasheet Download
