This part is a kind of semiconductor called 1N5956B.

Function of this product has 1.5W ZENER DIODE.

Manufacturers : WON-TOP ELECTRONICS

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® WON-TOP ELECTRONICS Features  Glass Passivated Die Construction  1.5W Power Dissipation  3.3V – 200V Nominal Zener Voltage  5% Standard Vz Tolerance  Low Inductance  For Use in Voltage Regulator or Reference  Plastic Case Material has UL Flammability Classification Rating 94V-0 Mechanical Data  Case: DO-41, Molded Plastic  Terminals: Plated Leads Solderable per MIL-STD-202, Method 208  Polarity: Cathode Band  Weight: 0.35 grams (approx.)  Mounting Position: Any  Marking: Type Number  Lead Free: For RoHS / Lead Free Version, Add “-LF” Suffix to Part Number, See Page 5 1N5913B – 1N5956B 1.5W ZENER DIODE Pb ABA D DO-41 Dim Min Max A 25.4 B 4.06 5.21 C 0.71 0.864 D 2.00 2.72 All Dimensions in mm C Maximum Ratings @TA=25°C unless ot [ ... ]

1N5956B PDF Datasheet Download