PUNCTURE PROOF INNER TUBES. Material Puncture Proof Foam. FIT Tube 12 x 1.75 - 2.1/4, ETRTO 47-203, RIM Width 20 mm, Tolerance +/- 1 mm. Stop-a-Flat puncture-proof inner tubes ensure you will NEVER have a flat tyre again!Hard-wearing, long-lasting and highly practical, Stop-a-Flat has been designed to be used across arange of light-weight applications and is ideal for, amongst other applications, children’s bikes,buggies, pushchairs and cycle trailers.
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