The most powerful (in terms of specific impulse) common storable propellant. It is composed of a stoichiometric ratio of hydrazine and nitrogen tetroxide. It has a specific impulse of around 290 seconds at sea level, and 340 seconds in a vacuum. Nitrogen Tetroxide vaporizes at 70 deg. F, so it may not be suitable for use in perpetually warm climates. Likewise, hydrazine freezes at 34 deg. F, so it cannot be used in perpetually cold climates. The density of the fuel mixture is quite high, around 1.3 g/cc.