There are four different types of trailer hitches, all of which range from Class I to Class IV. The higher the class at which the hitch is rated, the stronger tow capacity it has.
The hitches vary according to the amount of tongue weight and gross trailer weight the trailer can manage. Also, the tongue weight of the hitches varies according to the type of vehicle to which they are mounted. For example, Class I hitches on smaller vehicles, may have 100-lb. tongue weight while a larger vehicle with the same hitch may have 200-lb. tongue weight.
The gross trailer weight relates to how much total weight, including the trailer, the vehicle will be able to pull safely.