A 40.2 MB zip archive named TunaPro, which gives no device model, board number or file contents. The name suggests it may be a service or repair tool rather than a schematic or dump, but that cannot be confirmed from the title alone. Open it and inspect the contents before use, and scan any executables for malware. If it does contain firmware, compare model and version details with the target device before writing anything to it.
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 @mrepairo. Enginerys does not host this file.
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Compressed archive that every operating system opens without extra software.
Built-in OS tools7-Zip