Meter Star 2.25INCH/57MM OD Metal BBQ Stove Knob for 0.31INCH/8mm Shaft Valve Zinc Alloy knob,Backwards 14.98$
Gikfun Rotary Encoder Switch EC11 Audio Digital Potentiometer Handle Length 20mm with Knob Cap for Arduino DIY (Pack of 4) EK2045x4C 14.89$
uxcell a13041000ux0108 Silver Tone Top Rotary Knobs for 6 mm Dia. Shaft Potentiometer, 10 Piece, 19 mm, Black 19.52$
EVTSCAN 5PCS 2 Position Round Rotary knob Selector Switch, 16mm Mounting Size, AC 250V 3A or DC 30V 5A, for Industrial Control Panels 16.14$
UKCOCO 10pc Potentiometer Assortment 10K Ohm Breadboard Trim Potentiometer kit with Knob for Arduino 9.01$