T-Rex Racing Black Anodized Aluminum Spools or Swingarm Sliders 6mm Spools or swing-arm sliders are bolt-on accessories to the rear swing-arms of the bike. The operator will lift the bike with the rear stand from the spools. Most bikes come with pretreated holes for spools. The above picture is only a representation of the many different colored spools. This auction is only for one pair of spools. We have Black, Blue, Orange, Red and Silver. Please pick a color by sending us an email or leave us a note during checkout. We will send out Black spools if color of choice is not picked.