Shaft collar

A shaft collar is like a fancy ring that goes around a metal rod called a shaft. Picture your finger being the shaft and a bracelet being the collar. They get attached to the shaft and they help keep things in place. They can stop the shaft from moving too far in one direction by acting like a wall. They are often used in machines so that different parts don't move around too much and can stay in the right place. They can also be used to hold things in place like a bicycle wheel so it doesn't wobble around. So, a shaft collar is basically a little metal ring that helps machines work better and keeps things in the right place.