[Mr. Anderson]

Well from personal experience...no you definetly do not want to use N2O in fifth gear as that is an overdrive gear and can't handle the power too well. First gear is completely useless unless you like to buy tires alot, or you just want to put on a smoke show. What kind of car are you considering putting this in? My Zex kit activates at WOT (Wide Open Throttle) which is activated by a toggle switch (you're watching too many movies). So you hit the toggle and when you gun it the NOS kicks in. What I do is activate the switch right after I shift into second.. get up to about 4k and punch it......zoom zoom! When your done racing flip the toggle off. Yes there are such things as the push buttons, but you don't need that. PWMAN hit the refills on the head.. however when your tank gets down to about 3lbs or less your nitrous isn't performing to what it is capable of because of lost pressure. Below 2lbs is close to nothing at all! And to furthermore.. if you are going to be using this on the street alot (which you shouldn't be) invest in a remote bottle opener, of course if it is going in a trunk? It's a pain in the ass when some dipshit pulls next to you and your bottle is off! Hope I helped........