Short PDF of 130 KB named 274002, a bare number that gives no device, brand or part information. It sits in the schematic category, and its similarity to the neighbouring 274001 and 272001 files suggests a series of related documents from the same source, possibly datasheets. Open it to identify the subject before use. Any pinout or circuit data inside should be applied only after matching the part markings or board labelling exactly, since numbered documents are easy to confuse.
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.