This is a modified R8 version of my 3034 Lite Rail MT3, tool holder. This one holds R8 collets, end mill holders, etc. The screw spacing is set up for 3034 Lite T slot rail, but can easily just be screwed into a wall.
I havn't finished printing the test version yet. After it comes off the printer, there may be a few dimensional changes depending on how it goes.
It me need some supports in the screw holes and in the hollow openings underneath.
The author remixed this model.