Datasheet in PDF form for the 2SK1067, a member of the 2SK family of N-channel FETs, at 144 KB. The file carries no further details in its name. Its likely content includes maximum ratings, thermal data, characteristic graphs and a pin diagram. Repair work uses this to confirm which leg is gate, drain and source, to judge whether a measured resistance indicates a failed part, and to select an equivalent. Check package type and voltage rating before replacing it in power or audio stages.
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.