Sutong China Tires Resources TUN4009 HI-RUN Heavy Duty Lawn and Garden Tube, 18/850-8 Tr6-Inch Lawn and garden tube Fits 18x8.50/9.50-8, 18.5x8.50-8, 18.5x9.50-8, 20x8.00-8 and 20x10.00-8 Tr6 valve stem 18/850/950-8-Inch Tube