Скачать или смотреть How To Test Skateboard and Rollerskate Wheel Hardness

Shore A scale hardness is the most typical hardness scale used to measure the hardness of skateboard and roller skate quads wheels.

The higher the number, the harder the wheel, and each scale is tuned to be sensitive for a particular hardness range. The range of each scale is 0 to 100...
Here is a a Sure A Durometer Digital Hardness Scale Tool, and how to use it.
Just press the measuring pin repeatedly and it shows the values.
Here we see the first set at about 94A, the red set at 87A, and the last set at about 85A
You can use this as a way to test for wheel hardness, or for quality control on batches of skateboard wheels.
Those soft red wheels a beginner might like as they offer much more rolling resistance, where a more experienced rider typically wants a more responsive, efficient ride that harder wheels can give.