Axle Cap Nuts
Push-On Hat Retainers, Axle Cap Nuts, and Top Hat Nuts are strictly retainers rather than nuts, but are referred to as nuts. They are normally used to locate some object (such as a wheel) on a shaft. The shape is similar to a top hat.
Axle Cap Nuts Diameters
Axle Cap Nuts are available on the FCH Network with Imperial/US diameters that range from #1 to 1 1/4 and with Metric diameters that range from M4 to M12. The length of Axle Cap Nuts is usually measured from the point to the underside of the head.