Listed under schematics, this 110 KB PDF is named for the 2SD1347, an NPN bipolar transistor in the Japanese JIS 2SD series, and is probably its datasheet. Inside one would expect maximum ratings, electrical characteristics such as gain and saturation voltage, and an outline drawing. These help with out-of-circuit testing, lead identification and choosing a cross-reference with equal or better limits. The name states nothing about manufacturer or package, so confirm those against the original part.
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.