Brand: Matter Model: Matter Defcon Aditional info: Matter Defcon inline speed skate wheels have helped secure road and track World records. Joey Mantia Andres Munoz and Kalon Dobbin have ridden Matter Defcon wheels to victory.Whether sprinting or skating long distance Matter Defcon are found. Matter Defcon Wheels aren’t just track wheels anymore. Matter uses an F-Scale for hardness ratings. F0 F1 F2 F3 & F4 from hardest to softest. Each individual wheel in the Matter family will differ in hardness. Meaning a Juice F1 will not be the same hardness as a Lethal F1. In some cases IW has provided estimates on hardness ratings to help when searching for wheels. If provided these have been done with the assistance of Matter.