As I recall, most of the Mk I skis were black with elegant white lettering. It was a versatile recreational ski meant to compete with the Head 360.
Mk II VCE was the race ski, in slalom and GS flex depending on length. VCE stood for variable cracked edge.
Mk III was stiffer "midlength" version of the Mk I.
Mk IIIS was a full-length soft ski. In the days before fatties, this was the choice for powder skiing and for bumps if you were man enough to want to ski bumps on a 205.
Mk IV was a rowdy bump ski, a short stiff slalom with a turned-up tail. We'd call it a twin-tip today. At one point this was the best-selling ski in North America.
Mk V? I think it was a GS cruiser.
Mk VI was an overdamped slalom ski, the best example ever of a ski so overdesigned as to be practically useless. It was dead, dead, dead.
Mk VII was the only ski in the group without a laminated wood core. It used a polyamid honeycomb core -- as light as aluminum honeycomb without the harshness. Relatively light, sweet high performance ski.
Anyone who wants to correct or elaborate, jump on in!
Olin Mark Series Skis
I thought some of you might enjoy a look to bring back some hopefully nice memories from the 70's into the 80's.... These were the CT built Olin's.