Another important accessory is the hitch ball. Most hitch balls come with a plating of stainless steel, chrome or zinc, and can be protected, when not in use, by a rubber cover. The shank of the hitch ball fits through a hole in the ball mount. Then the two pieces are secured with a nut and washer. The hole in the ball mount comes in different sizes, so it's important to match the shank diameter with the specs on your mount. The same is true of the coupler, the front part of the trailer that connects to the tow vehicle. It will only accept a hitch ball of the correct diameter.
Many towing product companies offer interchangeable hitch balls. These sets come with either two or three balls, each with a different diameter. This makes it possible to accommodate different kinds of trailers with different kinds of couplers. Most interchangeable hitch balls feature a quick-release, positive-latch design, making it easy to change hitch balls without any tools.
But how do the hitch ball and ball mount connect to the trailer?