Quote Originally Posted by David Ruby
...What are the differences between "Universal", "V-Track", "Slim Track"?...
You can read about the Saunders easels at http://www.tiffen.com/Header_page_Saunders_Easels.htm. I have one of the "clutch drive" models, the UA1114 and love it. The 1-inch base works under autofocus enlargers, too.