PDF of 135 KB for the 2SC5277, filed as a schematic but most likely a transistor datasheet, as 2SC is the JIS prefix for NPN bipolar devices. Expect pin assignment, package dimensions, maximum ratings and characteristic curves. During repair it helps identify leads for diode-mode testing, check whether the part was overstressed, and look for an equivalent. Verify the marking on the installed part, because near-identical numbers can have different packages and ratings.
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.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.