Dukes Dispatches, Manufactured by our partner factory to the high standards and demands of riders in the UK,  Listening to customer feedback and our own team of test riders, we picked firmer and thicker grade of rubber to increase puncture resistance whilst still allowing for a quality ride.  We reckon our tubes are amongst the best on the market and our current test riders do hundreds of miles a year on them. tested and fitted on Super 73's, Unimokes, Rad bikes, a many other 20x 4" fat tyre bikes. and all tubes come with a free sticker for your bike  We're proud of our tubes and we inspect every single one of them before posting out.  However if for some reason you aren't 100% happy with our product, you have my guaranteed support to resolve the issue. Dukes Tyres & Tubes are a UK based start-up business set up to support the UK 20"x 4" fat tyre community.  our stock is ready to ship immediately the same Day. Collection and same day courier services offered within the DN Postcode Area.