Large 143 MB ZIP that by name contains PADS 9.5.1, the Mentor Graphics PCB design suite, and its schematic and layout tools. Some board design files used in repair, including PADS layout .pcb and ASCII exports, require this software or its viewer to open and inspect nets, layers and component placement. Technicians mostly use it to view the occasional layout supplied in PADS form instead of a boardview. Verify licensing terms, scan the package before installation, and note it targets older Windows versions.
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 @boardview_software_download. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.