Ride on Mower inner tube with a straight rubber valve TR13. These inner tubes are common for small ride on lawn mowers and Garden trailers. 18x8.50-8 TR13 (Straight Valve) Inner Tube. INNER TUBE WILL FIT: 18x7.00-8 - 18x7.50-8 - 18x8.50-8 - 18x9.50-8 - 18x11.00-8.
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