The Sector 9 65mm 80a Butterballs
Durometer is the measurement of how soft or hard a wheel or bushing is. All wheels are placed on a scale ranging from 75a to 101a. The lower the number, the softer the material. The higher the number, the harder it is.
Softer wheels are 75a - 78a. These roll slower, but allow more grip, making them popular in cruising and carving. These durometers also reduce vibration from bumpy roads for smoother skating.
The Riviera Prebuilt Dineh Drop Through Longboard
Wheels rated between 80a to 83a are balanced between soft and hard, giving the rider the freedom of control, speed, and grip. These are popular for freeriding, downhill, sliding.
The Arbor Sucrose Initiative Vice 69mm 80a White Wheels
Harder wheels (84a to 88a) roll fast and break into slides quickly, making them ideal for technical sliding. These durometers do not absorb vibrations and are recommend for smooth pavement.
To learn more science behind the wheel durometer, check out articles Part One and Part Two.