This part is a kind of semiconductor called F20LC30.
Function of this product has SF20LC30.
Manufacturers : Shindengen
Image and pinout :

Some of the text within the PDF file :
SHINDENGEN Super Fast Recovery Rectifiers Dual SF20LC30 300V 20A OUTLINE DIMENSIONS Case : FTO-220 Unit : mm RATINGS Absolute Maximum Ratings (If not specified Tc=25) Item Symbol Conditions Tstg Storage Temperature Tj Operating Junction Temperature VRM Maximum Reverse Voltage IO Average Rectified Forward Current 50Hz sine wave, R-load, Rating for each diode Io/2, Tc=112 I FSM Peak Surge Forward Current 50Hz sine wave, Non-repetitive 1 cycle peak value, Tj=25 Vdis Terminals to case, AC 1 minute Dielectric Strength TOR (Recommended torqueF0.3N¥m) Mounting Torque Electrical Characteristics (If not specified Tc=25) Item Symbol Conditions VF I F=10A, Pulse measurement, Rating of per diode Forward Voltage IR VR=VRM, Pulse measurement, Rating of per diode Reverse Current I F=0.5A, [ ... ]
F20LC30 PDF Datasheet Download
