Hand-me-down towing parts, what is here?

[BCnomad]

Also, the more miles your family tows, the more comfortable you get with the feeling of having the trailer push your truck around a bit.

[Brian B-P]

Originally Posted by SouthernCamper

OK well I know this is a hitch, a sway bar, and equalizer bars, right? I just don't know what kind they are, if they are what we need, and what else we need that's not pictured.

A head (with ball) and shank of a weight-distribution (WD) system, a sway control device, and the spring bars for the WD system... if you want the correct terms for clarity.

In case there's still any information needed on what the parts are, the weight-distributing hitch is the round-bar style (the other common type is trunnion), of the most basic design (spring bar ends connect to the trailer frame brackets with chains). The head (part which holds ball and has sockets for bars) and shank (the part which slides into the hitch receiver) are there, but not the trailer frame brackets.

If you decide that you want to use a WDH, and that this type is desirable:

• the missing trailer frame brackets would be needed, and don't even need to match the rest of the WDH,
• the only difference between weight ratings in most brands is just the stiffness of the spring bars, and replacement bars are available (but must match the head)

Here's an example (from eTrailer) of this style of system:
Pro Series RB3 Weight Distribution System with Shank - Round Bar - 10,000 lbs GTW, 750 lbs TW (online from eTrailer) or Pro Series 49582 (manufacturer's site).
To use what you have you would need to at least add the trailer frame brackets - I don't see the brackets corresponding to this example system separately at eTrailer, and even the manufacturer doesn't offer them.

If the spring bars are not right (such as too stiff, because they are intended to transfer more weight between axles, for use with a trailer having more tongue weight), then replacements are available. For the example above, 550 lb bars (part 58439) are available (e.g. from eTrailer), but the bars plus brackets will likely cost as much as a whole new system.

Almost all conventional WD system heads have a place to mount that small ball for the tug end of a sway control device. These sway control devices are only used with WD systems that don't have a built-in sway control feature (just extra friction between some parts) and are pretty generic, so you can mix and match sway control and WD brands.

You need a 2" diameter ball; the one in that head might be either 2" or 2-5/16". balls interchange as long as the diameter of the shank (threaded part) matches; it is probably 1" diameter (normal for Class 3 towing components).