THE PERFECT REPLACEMENTS: CalPalmy offers the perfect replacement inner tube for 4.00-6" tires of hand trucks, lawn mowers, yard trailers, and wheelbarrows PREMIUM QUALITY: Our inner tubes are made of premium, heavy duty rubber, yet for less cost from the OEM GUARANTEED PROPER FIT: Our inner tubes are approved by the mechanic to ensure the quality meets or exceeds the OEM EASY INSTALLATION: It takes less than 5 minutes to replace all tires