Safefill cylinders. How big will fit?

Juramalt

The smallest safefill cylinder is 5KG. A bit too small to last a week in winter. IWould need two. Will the 10KG one fit in the locker of my Bailey Pageant series 6?  I can't take the caravan to the gas place as it's pretty tight down there. So if anybody
knows the answer it would be a help.