The DTM core is another of our UNIQUE designs where we combine OUR original invention of the HollowTech cores with the spoke cores. Part of the core is a HollowTech core, in the middle, where the size of the wheel and our Brand name is Laser Etched. Cores are Anodized Black. Our new Radix Line that will set the new standard again and will change the scooter sport for ever; like we did before... The 30mm wide wheels will replace the 24mm inline skate size wheels as it will give the user more grip, more angle, more control and more air time! The Radix Line wheels are available in 3 different hardness: SOFT, MEDIUM and HARD ! SOFT: just below the ?standard? hardness of the ?regular? scooter wheels for most smooth riding and super high grip. MEDIUM: Equal to the ?standard? hardness HARD: Just above the ?standard? hardness ideal for warmer areas and smooth surfaces like the skate park. Fits the Eagle Supply, District and Addict forks and decks. More brands will follow. Eagle Supply will supply you with all spacers needed for any brand on request. EACH MODEL HAS DIFFERENT HARDNESSES FOR INDIVIDUAL CHOICES.