Part datasheet in PDF for the MJE13007F, a high-voltage NPN switching transistor. The F suffix usually denotes an isolated fully plastic package, though the name states nothing beyond the part number. These transistors are common in compact fluorescent lamp ballasts, chargers and small off-line switch-mode supplies. The document lists voltage and current limits, gain, switching speed and pinout, letting a technician confirm an equivalent. An isolated-tab version can be mounted without an insulating washer, so check which package the board was designed for.
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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