Ender 3 20mm thin spool holder new design without threaded nut

Ender 3 modified spool holder to fit in thin spools 20mm diameter designed to fit in the new original nut without threads of the ender 3 printer, it´s as large as original one.
I printed it in PLA with tree support upside down from how is it in the stl.
Sorry but the real object images are stretched