Hi Dick,
If you use the search feature you will find an abundance of posts on WD hitches. There are many types, but for a quick reply you can look at 3 in particular. The first and most expensive is the Hensley Arrow. The next is the Reese dual cam and the third is the Equal-i-zer brand.
You will find many posts on who uses what type and why they chose it. Most folks are very happy with their hitch and some are extremely brand loyal. I use the Equal-i-zer as I find that it is very easy to setup and offers both WD and sway control in one unit for simplicity.
The basic premise of a WD hitch is to have the hitch head that is attached to the TV at a downward angle, allowing the weight bars that are attached to the trailer to 'torque' the hitch receiver and thus the TV frame. This torqueing action will re-distribute some of the tonque weight off the ball and to the front axle of the TV and a small portion back to the trailer axles.
Hope this helps a little. Have fun in your search!
