QualityParts From Oregon That you can depend on. Universal fit for most 13" tires with 6" rims: Made of quality, long-lasting butyl rubber; Straight valve stem; Visually inspect the valve stem for premature wear. There is no specified interval to replace a tube, when a tire is replaced, carefully inspect tube for wear - cracks or other damage.; ; ; Oregon Equipment Parts 71-096 Innertube 13X500-6 Straight Va