A 98.4 KB PDF named 16TTS_FP and filed among schematics. The name holds no device, board number or revision, only a component code with an FP suffix that probably denotes a package variant of the 16TTS series. That series follows International Rectifier thyristor naming, so the content is most likely datasheet material covering ratings, characteristics and case outline. Technicians use it to check pinout and mounting when swapping a part, and should confirm the suffix on the original component matches.
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.