There is $20 minimum order for physical goods, and knob orders typically ship out on the weekend.

This listing is for 15mm solid aluminum knobs. They have a 1/4" smooth shaft with set screw (uses 5/64" or 2.0mm  hex screwdriver). FREE SHIPPING to anywhere in the United States & territories.
 
The knob colors currently available are Red, Orange, Deep Gold (black or white marker), Yellow, Light Gold, Blue, Purple, Black, Silver, Gray, and Champagne. I plan to add more colors over the coming year.
 
1.57 each for quantities between 25 - 49
1.46 each for quantities between 50 - 74
1.35 each for quantities between 75 - 99
1.25 each for quantities more than 100
 
These are the knobs I have used on all VFE Pedals since 2015. I am making them available to purchase so that I can add more colors, sizes, and types to my classroom knob inventory.