Easy to rearm and yes it will push it out to green when treaded on. It is not much good without it or not wearing it . Correct kit and fits rearm yours too!
instruction need to be clearer the small ring is dropped in the canister housing and you simply screw it tight the color will change to green be cafefull where you store life vest as they will ' deploy in fishing locker after a rain ,as most are not waterproof.