its LAUGHABLE, just a scam to get more dollars out of ya.
Firstly unless your a V8 supercar driver hitting over 200km most of the time, you'll not see one once of difference in handling or braking under extreme conditions. Secondly it doesn't improve the life of the tyre by penertating the rubber (thats just plain silly) or the stuff would leak straight out. Thirdly it won't get you any more life out of your tyres then running them at the correct pressure as recommended by the TYRE manufacture, not the vehicle manufacture. Fourthly, the air we breath is 70 odd percent nitrogen anyhow (22 % oxygen and a mixture of a few others) and when they pump your tyres up they don't pull a vacumm after the tyre is beaded up on the rim, before they do the nitrogen fill and therefore can't gurantee a 100% nitrogen anyway. And lastly, every tyre shop and every servo would have it' if wasn't just a money making scam.
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