CR-10 extruder knob with a differece

An extruder knob with a difference this one will not slip on the shaft so easily.
The problem with plastic knobs is they have little strength where it counts and are generally designed to large. The result is they turn on the shaft
The knob doesn't need to be very large as the shaft turns easily anywhay, it also has an indicator point so you can easily see the knob turning good for when the extruder retracts.

You will see there are 2 thin slots under the knob this is where you hammer in 2 s