Lockjaw

Yeah it's just an air suspension system. Instead of the standard coilsprings you mount airbags like big rigs use. You can lower the car by letting the air out of the airbags, and you can lift it to normal ride height by airing it up. They get aired up by a air tanks which in turn are filled by an in car compressor usually mounted in the trunk. It's pretty trick actually.

Oh and in Cali air supsension ARE legal as long as like any other lowered car they are not operated on public streets at an illegal height(aka slammed to hell)

http://www.chp.ca.gov/html/streetlegal.html

Thank the Lord I live in a state that as long as you aren't making an ass of yourself the cops will leave you alone with your mods.