NOS is illegal on the streets. If you get caught using a bottle, expect a MASSIVE fine ($10,000) and a possibly a jail sentence.
not just that but also any of the equipment used facilitating the use of NOS
on the other hand i know 5 ppl who use it on the street and they've never been caught, thanks to some tricky piping and bottle placement
and its not that big of a fine, its usually just them ordering oyu off the road and you have to get an engineer to inspect tht you dont have NOS anymore... not to denote how serious it is when you get caught with nos but - they will make sure you dont have a car for about 3 months, they just keep bombarding you with paperwork