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It is very flexible.
Not easy to be wear and tear.
It is made of rubber,can withstand a great weight
Material: Rubber + Metal
Wheel OD: 68mm
Wheel wide: 24mm
Bearing ID: 6mm
Axles: 40mm
Package include:
2 x wheels
4 x bearings
2 x wrenches
2 x bolts
4 x washers