Assuming you mean the best weight-distributing hitch with built-in sway control, there are several good ones with one being the best but also most expensive.
Best is probably the ProPride, along with its predecessor the Hensley Arrow. Absolutely no sway, and excellent weight distributing. But the ProPride retails for $2,345, and the only source for a new one is the manufacturer.
Trailer Sway Elimination | Sway Control | ProPride, Inc.
The ProPride is the newest redesign of the original Hensley Arrow. The Hensley Arrow is still for sale by:
Hensley Mfg., Inc. - Trailer Sway Eliminated...Guaranteed
Second place goes to several that all cost about $550 to $650 each from a discount hitch source:
1] Reese Strait-Line Trunnion bar dual cam.
http://www.etrailer.com/dept-pg-Weig...des_Shank.aspx
Note that Reese makes a few different weight-distributing systems. Don’t buy anything Reese sells except the Strait-Line Dual Cam. The rest are less expensive, but don’t work as good.
2] Equal-I-Zer
Amazon.com: Equal-i-zer 90001200 Equalizer Hitch: Automotive
Some folks swear by these. I prefer the Strait-Line dual cam.
3] Husky Center-Line
Amazon.com: Equal-I-Zer hitch
Highly rated, but I have no experience with these. Note that you buy the head and then add the spring bars of the correct weight capacity.
4] Blue Ox Sway Pro
Sway Pro - Blue Ox Weight Distribution Hitches on Sale - PPL Motor Homes
Blue Ox is a big name in towing for a lot of years. They don't sell an "economy" hitch, only the good stuff.
What do I have? ProPride for my travel trailer, and Strait-Line for my cargo trailer.
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Grumpy ole man with over 60 years towing experience. Now my heaviest trailer is a 7'x16' 5,000-pound flatbed utility trailer, my tow vehicle is a 2019 F-150 Lariat 3.5L EcoBoost SuperCab with Max Tow (1,904 pounds payload capacity).
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