HARZOLE Tire String Plug JT-4001B500 Tire Plug for tubeless ￠6 4inch Black 100mm 500 pcs ￠6 4" black, 5pcs/card, 100pcs/box 5 Boxes For most radial tire emergency repairs Install inserts using split-eye needle Tire Plug inserts can be used on passenger or truck tires. Radial or Bias-Ply tires. Made from butyl rubber, these inserts are very strong, allowing easy insertion through steel belted radials. Tire Plug inserts are for temporary repairs, sealing by compression only.