When upgrading to X axis 12mm rods, double bearing that could be found on one of there platforms is not great. Bearings are very loose and one side is open so potentially can slide out. Other problem is no easy way to attach cable chain. So I remodelled this with tighter fit for 12mm axial bearings and I added holes to the top for 3mm threaded insert to enable cable chain attachment.

Model comes with snap off back which enables to be printed in 45deg orientation for stronger layers. (not that it is needed, but its just my standard approach). No additional support needed. It will require small bit of clean-up after back fin is snapped off, but its very easy to do with scalpel.

Print on chamfered/beveled edge