3 Lobed Threaded Through-Hole Knob with Brass Threaded Inserts

This is a durable, customizable knob. It features a hole sized for a metal threaded insert for extra strength. The holes are sized for inserts with 8-32 threads.. I used these 8-32 threaded inserts from amazon and you'll need a soldering iron or such to install them. 

Print Settings
Printer: Prusa MK3  
Material: PETG, ABS, or PLA+ recommended  (I used this PETG Filament)
Layer Height: 0.2 mm  
Supports: On underside of knob 
Infill: 50%+

Perimeters: 3 min Recommended