Vivitar Matched Multipliers

[dynachrome]

In the early 1980s Vivitar sold 2X teleconverters for certain zoom lenses. They were called Matched Multipliers and each one had the name of the lens it was supposed to go with engraved on its side. I recently got a Vivitar 100-200mm f/4 Close Focusing zoom and the Matched Multiplier for it. These Matched Multipliers were fairly standard 4 element models and should not be confused with the later Vivitar 2X Macro Focusing Teleconverters. I'm sure I have a number of Matched Multipliers here somewhere already. When I look at pictures of the Matched Multipliers online it seems that whether one is marked for the 70-150, the 70-200, the 75-205 or the 100-200, they look identical. Are they? When I was in High School I had a Soligor 2X teleconverter for my Konica. Teleconverters at that time were not made for lenses that short. How well did it work? It was passable when the standard lens was closed down to f/8 or f/11. The 85/1.8 Hexanon I got years later was much better. I realize that using teleconverters on slow zoom lenses is a dicey proposition at best. I'm more interested in the 100-200 for its close focusing than for the possibility of using it with any teleconverter.