PDF sheet for the BC557 general-purpose PNP transistor, the name giving its minus 50 V and minus 100 mA limits, filed under schematics at 45.8 KB. The document should list pin assignment, TO-92 package outline, gain groups and maximum ratings. It is handy when identifying a part on a board, confirming the collector, base and emitter order before fitting a replacement, or selecting an equivalent PNP device. Gain-group letters printed after the number can affect biased circuits, so compare them with the original component where it matters.
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.