I managed to get hold of one of these today (few in stock in a store in Manchester). Tried it in the Hilo just now, we have a LWB so the length is perfect but it is a fraction too wide. It will do the job but is does press against the canvas slightly on the sides so I do wonder if it's raining whether that would cause the water to transfer through.... It's not perfect but it's the narrowest mattress I could find after hours of searching!Looks like the perfect solution. Thank you... sold out at decathlon- hardly surprising during lockdown, but will get when back in stock.