Wolanksi LowBoy focusers, as Gary says on his web site, the lowest commercially available focuser in the world. Minimum height is just 3/4" above the tube.
On the left is a custom unit with a flat, circular baseplate. It is drilled and tapped for 3 #6x32 screws. Should replace the older, Delrin Teleport focusers as is, no new holes required. But of course it's good for any flat mounting. This one comes complete with the adapter. Condition is excellent, less than a year old and not worn. New this one is $105, actually $121 if shipped to US. Asking $85 shipped in US. (SOLD)
On the right is an older one of the same design, but with more mileage and no adapter. It also has a patched hole where I broke off my #6x32 tap attempting to widen the set screw hole for the Nylon set screw and had a heck of a time getting the remnants out. It's also about 2 years old and has seen more use but otherwise is in fair to good condition. It has the standard baseplate which can be bent to fit a tube. Still a great focuser though, and smooth, or I wouldn't be selling it. Asking $40 shipped in US. (SOLD)