extended bracket for kossel spool holder

I liked ChrisParish's kossel spool holder(https://www.thingiverse.com/thing:996476), so I designed extended bracket to fit mine.
This design can be used for any 2020 extrusion up to 300mm. If you need a larger one, let me know.

EDIT 31/12/2017 :
Added CAD file (.STEP)