Class IV hitches is very similar to Class III hitches except for the weight ratings. Class IV hitches are weight carrying (WC) and weight distributing (WD) hitches depending on the vehicle and hitch specifications. Not all Class IV hitches are rated to be both. The hitch specifications will alert you to a hitch that is not weight distributing. Class IV hitches used as weight carrying is rated up to 12,000 lbs. gross trailer weight (GTW) with a maximum trailer tongue weight (TW) of 1200 lbs. Hitches that are used for weight distributing are rated up to 15,000 lbs. gross trailer weight (GTW) with a maximum trailer tongue weight (TW) of 1500 lbs. This style of hitch typically uses a 2" square receiver opening. The use of a ball mount and hitch ball of the same rating or higher is required for weight carrying. To use the weight distribution side of the hitch a weight distribution system is required. Class IV hitches attach to the vehicle frame only. Always consult your owner's manual for vehicle rating.