This part is a kind of semiconductor called 1N4148W.

Function of this product has SURFACE MOUNT SWITCHING DIODE.

Manufacturers : Diodes Incorporated

Image and pinout :

Some of the text within the PDF file :

Features  Fast Switching Speed  Low Forward Voltage: Maximum of 0.715V at 1mA  Fast Reverse Recovery: Maximum of 4ns  Low Capacitance: Maximum of 2pF  Surface Mount Package Ideally Suited for Automated Insertion  For General Purpose Switching Applications  Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)  Halogen and Antimony Free. “Green” Device (Note 3)  Qualified to AEC-Q101 Standards for High Reliability BAV16W/1N4148W SURFACE MOUNT FAST SWITCHING DIODE Mechanical Data  Case: SOD123  Case Material: Molded Plastic, “Green” Molding Compound; UL Flammability Classification Rating 94V-0  Moisture Sensitivity: Level 1 per J-STD-020  Terminals: Matte Tin Finish Annealed over Alloy 42 Leadframe; (Lead-Free Plating). Solderable per MIL-STD- [ ... ]

1N4148W PDF Datasheet Download