Plastic hubs on metal shafts with no bearings like the OEM wheels, likely means the plastic will wear faster.
Cheaply priced (as opposed to others)
so they are good for me to use, especially since my mower is on its last leg, or wheel, if one prefers.
Theses are easy to use and get my glasses clean in a jiffy.
Convenient small packages, so they fit just about everywhere and I can take a few with me.
The price is worth it to me for clean glasses.
Thanks Zeiss