We have both kinds. The more expensive one has steel handles and a heavier gauge tub. It weighs a good bit more, but I couldn't say how much more.
Everything but the wheel comes from PA in the USA. The wheels come from China. No US supplier makes the wheels. https://www.pennlive.com/news/2017/06/ames_company_harrisburg_wheelb.html. The link is to a web article discussing Trump's visit to the factory in 2017. They reference the wheels in the article. "The company is dedicated to using American suppliers, but none currently exist for the small tires needed for the front of the wheelbarrows, Babbs said. That's the only part of the wheelbarrow that isn't U.S.-made, he said. It's something Trump could seek to remedy through competitive trade policies, which was part of the discussion during the president's visit."
In the case of metal,wire the smaller number will be thicker