this company is using for wheelchairs built in "low income" countries.
Well I would like to try that caster form some projects of my own. I
called the company and that don't and won't import any of the wheels
into the US so I was wonder if there is any possibility that some US
supplier might have something similar. They told me the wheels they use
can be 4 or 5" in diameter and are about 4" wide. Only about the center
third of the wheel is supported by the hub, the outer section is fairly
flexible to conform as it rolls over uneven surfaces. To get a look at
it, check out this youtube video. They show the wheel up close at about
1 minutes 7 seconds into the video.
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Also in the video they state that they found the wheel being used on
push carts in Zimbabwe.