Ian, just thinking outside the box here mate in an effort to help so please tell me to Foxtrot Oscar if you like......Fix a Flat can be used in a pinch and is mentioned because of its portabilty. Comes in small green plastic containers in the states. Its supposed to fill the tyre to a point that a car can be driven to a garage so a more permanent fix can be made. Not sure what or how the green ingredient is removed from the tyre once the product is used though. The other thing I've seen which is ingenious is the football type bladder that has a hose which connects to the exhaust and you place the bladder under the car where you need it and the exhaust fills up the bladder. This too is light and portable. Just suggestions made more for their storage ability in the car then their effectiveness since I've tried neither. I have AAA (like the RAC or AA) in the event of a flat.