Need CloudConvert to download photos from a .rar link??

A colleague from Morocco has sent me photos via a link at .rar (not .com, .gov, .net, etc). My system pops up with "Oops there was a problem with the preview" and I need an ap to open or edit the file. The selection list is CloudConvert, Document Viewer from Google Drive, and a suggested 3rd party ap Auth2.0 Playground. I'm not familiar with any of them and hesitate to download an unknown ap. Suggestions please?