This is from memory. I have files tucked away somewhere. I won't be the least offended if someone corrects me here.
The process of bonding aluminum was pioneered by De Havilland during the development of their twin engined DH-103 Hornet long range fighter (1945). The renowned and earlier all-wood DH-98 Mosquito equipped the De Havilland company with a lot of experience in bonding airframes together as opposed to using fasteners. This technology filtered down to other uses.
The company that produced Vitus was not the first first frame maker to build aluminum frames. But they along with the Italian frame maker Alan were the first to build them in large numbers. Both frames came out strongly at about the same time. These frames were from different manufacturers and different countries. No rebadging was involved.
The original Vitus Duralinox frame was conceived by a company called Alteliers de la Rives in the Loire valley, not far from Saint Etienne. This was an older company, and they had produced several, well-reputed lines of steel tubing using the Vitus name. When Ateliers conceived of a bonded frame made from 5086 Aluminum, they formed a cooperative partnership with two other companies to produce the tubing. Assembly was done by the French aerospace firm, TVT. They used a process of dry heat activated epoxy. The tubing was inserted into lugs using an interference fit.
The Alan is often differentiated from the Vitus as being "screwed and glued". But what is lesser known is that Vitus produced what they called their "A" line — their name for Services des Courses machines that were destined for delivery to racing stars competing in the European 'grand tour'. One of the most famous of these illustrious athletes was Sean Kelley. His physique, size and riding style were particularly suited to the Vitus frame.
The Vitus "979" Duralinox frame as well as the Alan are attended by horror stories of becoming catastrophically unbonded, but according to better authorities, there is no basis for them. Still, many have claimed that the frames should be ridden by lighter riders in sizes of less than 57 cms.
Both companies offered a number of anodize (aluminum oxide) colors on the triangle tubing — Vitus reportedly offering greater variety. Black, rose and blue are very common.
Both companies were frame builders. To avoid confusion, the enthusiast should keep in mind that Vitus and Alan frames bore many names but not always in addition to the bold decals that more often than not defined the frame-set.
Many of these frame-sets were built up by private persons and assembled with parts and components of choice. Other were painted to appear as team bikes — a reminder that in the great races of the time, what might appear to be a specific bike may have in fact been something else that was more appealing to the needs of a team cyclist than the one offered to him by the factory or team he rode for.
The 979 came out in two versions, the Mk I and MkII. It was produced from 1979 to the early 90's. Later models were known as the 992 — a development of the 979.
I own a late 80's 979 that was built up from a frame-set by a Japanese triathlon athlete. It is equipped with a mixture of Campy Record, vintage Suntour, Mavic, Cinelli and Shimano. Being what it is, this mix of parts should not be offensive to even the more fussy vintage enthusiast. But I would not mind if it did. I love my Vitus just the way it is.