Reference PDF for the 2SK1888 N-channel FET, 94.9 KB, catalogued as a schematic. The 2SK code follows the Japanese registration system for transistors, so this is a component datasheet for a single device. It gives what you need at the bench: which pin is gate, drain and source, the maximum ratings and the package outline, all useful when a power stage has blown and a substitute must be chosen. The file name states no maker, so match the part marking first.
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.
Any PDF readerSumatraPDFFirefox / ChromeFlexBV (links PDF to boardview)