This CURT adjustable ball mount has a shank size of 2" x 2" and features three different trailer ball sizes to accommodate all standard coupler sizes: 1-7/8", 2" and 2-5/16". The 1-7/8" trailer ball offers a gross trailer weight capacity of 6,000 lbs. and a tongue weight capacity of 600 lbs. The 2" trailer ball has a GTW capacity of 7,500 lbs. and a TW capacity of 750 lbs., and the 2-5/16" ball offers 10,000 lbs. GTW and 1,000 lbs. TW. This tri-ball ball mount also features an adjustable shank assembly with multiple mounting holes for varying ball heights. Each trailer ball can be raised to a maximum of 5-3/4" rise or lowered to a maximum of 5-3/4" drop, allowing you to make your trailer completely level in any towing situation. Material: Carbon Steel.