This is a mix of the original pulley and the PC-Blend Prusa Pulley. The wheel over the bold assures that the bolt and the wheel are not connected and cause friction. The wheel is also wider than the wheel so that is gets stuck in the pulley body.  

• Use M5 x 25 bolts
• Print with 6 perimeter walls
• 20% Gyroid infill
• Preferably in PC blend or PLA CF