This heavy-duty rectangular "Multi-connector" RS series was uised in various studio and control equipment consols etc. and the range comprises 8 pole through 30 pole in chassis and cable mounted arrangements with a slide-latch quick-release retention system.
Pending a full listing, various images may be viewed in this picture-gallery:
http://www.casa.co.nz/connectors/multipole/rectangular/Fujitsu/gallery/