This part is a kind of semiconductor called IN5399G.

Function of this product has 1.5 AMP GLASS PASSIVATED RECTIFIERS.

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IN15391G THRU IN5399G 1.5 AMP GLASS PASSIVATED RECTIFIERS VOLTAGE RANGE 50 to 1000 Volts CURRENT FEATURES * Low forward voltage drop * High current capability * High reliability * High surge current capability * Glass passivated junction 1.5 Amperes DO-15 .140(3.6) .104(2.6) DIA. 1.0(25.4) MIN. MECHANICAL DATA * Case: Molded plastic * Epoxy: UL 94V-0 rate flame retardant * Lead: Axial leads, solderable per MIL-STD-202, method 208 guranteed * Polarity: Color band denotes cathode end * Mounting position: Any * Weight: 0.40 grams .300(7.6) .230(5.8) .034(.9) .028(.7) DIA. 1.0(25.4) MIN. Dimensions in inches and (millimeters) MAXIMUM RATINGS AND ELECTRICAL CHARACTERISTICS Rating 25 C ambient temperature uniess otherwies specified. Single phase half wave, 60Hz, resistive or inductive [ ... ]

IN5399G PDF Datasheet Download