Indexed as a schematic, this 139 KB PDF actually concerns the 2SK2715, an N-channel field-effect transistor according to the Japanese JIS 2SK prefix. It should contain the part datasheet, with maximum ratings, characteristic tables and pin arrangement. A copy carrying a 1-5 suffix is listed separately and may differ in edition. Repair technicians use such sheets to identify gate, drain and source, to test for shorts correctly, and to choose replacements with equal or better voltage, current and on-resistance figures.
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.