i have just bid on some stuff called 'bitron tyre safety solution'. I first heard about this 4-5 years ago and they were trying to sell distributorships more than product and at the time they wanted about $40 for this. they claim it can repair holes up to an 1/8 of an inch and we were looking at it for a mate with a 3 wheeler who kept getting flats. anyone used it? and what about if you wanted to let some air out of your tyre?? will it seal up your valve? don't bid on it either you buggers.