With these you can replace the rubber cone bushings where your bar mounts attach to the triple clamps.
This is helpful if you're feeling a bit of play or slop at this connection. In our experience this can be noticeable and get annoying on KTM bikes after a while of hard riding, or if you have taller bars.
Or maybe you're looking for a more direct feel with precise feedback. You'll also have less troubles with the bar mounts twisting if you knock something.
You can also play around with using these rigid cones in just the top or bottom for a in-between feel.
The more rigid this connection becomes, you would notice a bit more vibration feedback into the bars, particularly on big-bore bikes.