Datasheet for the 2N3055, filed here under schematics as a 39.8 KB PDF. The 2N3055 is a classic NPN silicon power transistor, usually in a TO-3 metal can, found in linear power supplies, audio amplifiers and regulators. Technicians use the sheet to confirm pinout, maximum collector current and voltage, power dissipation and gain before choosing a replacement. Check the case style and the marking on the actual part, since different makers publish slightly different ratings for the same type.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
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