PDF reference, 67.1 KB, for the 2SD1627 transistor, stored in the schematic section. The name carries nothing besides the part number. The 2SD prefix follows the JIS scheme for NPN bipolar transistors used in low-frequency and power stages. Inside should be ratings, gain ranking and a dimensional drawing. Repair technicians use it to confirm the pinout before fitting a new part, to test junctions out of circuit and to pick an equivalent with adequate voltage, current and dissipation.
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.