Hitch Locking Pin fits all 2″, 2.5″, and 3″ receivers. The useable length of the pin portion is 3-1/2″ long (Regular) or 4-1/2″ long (Long), with a diameter of 5/8″.
The regular pin should fit most receivers; however, if you have a truck with a 3″ receiver with a thicker material, the long hitch pin will be a better fit for you. Heavy-duty or oversized receivers, such as those used in Class V hitches or commercial towing setups, may have thicker walls that increase the total width the hitch pin needs to span. In those cases, you should use the long hitch pin (WS05-L).