This part is a kind of semiconductor called S15SC4M.

Function of this product has Schottky Barrier Diode(40V 15A).

Manufacturers : Shindengen Electric Mfg.Co.Ltd

Image and pinout :

Some of the text within the PDF file :

SHINDENGEN Schottky Barrier Diode Twin Diode S15SC4M 40V 15A FEATURES ● Tj150℃ ● PRRSM avalanche guaranteed ● Small θ jc ●High current capacity OUTLINE DIMENSIONS Case : MTO-3P Unit : mm APPLICATION ● Switching power supply ●DC/DC converter ●Home Appliances, Office Equipment ●Telecommunication RATINGS ●Absolute Maximum Ratings (If not specified Tc=25℃) Item Symbol Conditions Tstg Storage Temperature Tj Operating Junction Temperature VRM Maximum Reverse Voltage VRRSM Pulse width 0.5ms, duty 1/40 Repetitive Peak Surge Reverse Voltage IO Average Rectified Forward Current 50Hz sine wave, R-load, Rating for each diode Io/2, Tc=135℃ IFSM 50Hz sine wave, Non-repetitive 1 cycle peak value, Rating of per diode, Tj=125℃ Peak Surge Forward Current PRRSM Pulse width 10μ [ ... ]

S15SC4M PDF Datasheet Download