I use mine on some yard carts that sit for a long time. I have never had a flat spot in either of 2 sets of tires. These are great for flat-free dependability.
I have no idea, but they're solid rubber. I'd check the weight limit of the cart I'm using them on, I'm sure they can hold whatever the cart can withstand.
Because these tires do not have any tubes in them and they are solid rubber, they should work just fine in any temperature. I have never put them to the sub-zero test, but I personally don't see any reason why they wouldn't hold up to those temperatures.
YES IT CAN.
Yes, these should work on that wagon. You may want to check the hub-size just to be sure.
They are 4 holes . Very, very good quality. They easily support my generator.
These 4 wheels are for a wagon. Pretty sure one of them would be much too small for a wheel barrow. Why not buy a single wheel intended for use on a wheel barrow? I think they are more like 16" wheels.
On my yard / garden cart, a screw on nut and washer tightened with a socket wrench secure each of the wheel assemblies to the 5/8" axial.
I don't know. I assume shipping costs. If you want an accurate answer I would suggest calling Customer Service.
Hub is the same as Tubed models of Chinese cart wheels, two to three inches long. (I would have to dis-assemble to make an exact measurement). The hub is offset which extends about 1/4 to 3/8-inch past wall of tire on one side. I disposed the old tube tires and hubs because they never held air but for a few minutes. These are an exact replacement but with sponge filled in place of air. Works so much better in my yard!