This is a three-position training wheel system, with tool-less installation and removal, so you're always the hero without so much as a screwdriver. Reinforcing this, the tubular steel arms are built to take a beating, while the foam tires will never go flat

• Closed-cell foam tires.
• Tubular steel arms.
• Compatible with 2013 and newer models of the Hotrock or Riprock 20-inch Coaster models.