This part is a kind of semiconductor called S3D.

Function of this product has SURFACE MOUNT RECTIFIER.

Manufacturers : General Semiconductor

Image and pinout :

Some of the text within the PDF file :

S3A THRU S3M SURFACE MOUNT RECTIFIER Reverse Voltage - 50 to 1000 Volts DO-214AB MODIFIED J-BEND Forward Current - 3.0 Amperes FEATURES ♦ Plastic package has Underwriters Laboratory Flammability Classification 94V-0 ♦ For surface mount applications ♦ Low profile package ♦ Built-in strain relief, ideal for automated placement ♦ Glass passivated chip junction ♦ High temperature soldering: 260°C/10 seconds at terminals 0.126 (3.20) 0.114 (2.90) 0.245 (6.22) 0.220 (5.59) 0.280 (7.11) 0.260 (6.60) 0.012 (0.305) 0.006 (0.152) MECHANICAL DATA Case: JEDEC DO-214AB molded plastic body over passivated chip Terminals: Solder plated, solderable per MIL-STD-750, Method 2026 Polarity: Color band denotes cathode end Weight: 0.007 ounce, 0.25 gram 0.103 (2.62) 0.079 (2.06) 0.060 (1.52) [ ... ]

S3D PDF Datasheet Download