This is one of the transistor types.
This part name is D2499, 2SD2499.
The package is TO-3P.
This product has Horizontal Deflection Output For Color TV functions.
The manufacturer of the product is Toshiba.
See the preview image and the PDF file for more information.
This is 600V, 6A, Silicon NPN Triple Diffused Mesa Type Transistor.
Some of the text files within the PDF file :
1. High Voltage: Vcbo = 1500V
2. Low Saturation Voltage : Vce(sat) = 5V (Max.)
3. High Speed : tf = 0.3us (Typ.)
4. Built-in Damper Type
5. Collector Metal (Fin) is Fully Covered with Mold Resin.
MAXIMUM RATINGS (Tc = 25°C)
1. Collector-Base Voltage : VCBO = 1500 V
2. Collector-Emitter Voltage : VCEO = 600 V
3. Emitter-Base Voltage: VEBO = 5 V
4. Collector Current : DC IC = 6, Pulse ICP = 12
5. Base Current : IB = 3 A
6. Collector Power Dissipation : PC = 50 W