RAR archive, 1.53 MB, for the Nokia 220 feature phone, covering hardware types RM-969, RM-970 and RM-971. These designations identify single and dual SIM or regional variants of the same model. The archive contents are not stated, though schematic or layout sheets are typical for this kind of file. They help trace the battery, charger and power-on circuits, locate keypad and display connections and find test points. Extract with WinRAR or 7-Zip and match the RM code printed under the battery before use.
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 @esquematicosparatodos. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.