N95 Evaporative Control System Required on all cars registered
in the State of California. NA for other states. $ 37.85
If it came on the car, Az will probably require it.
Does not really hinder performance. it just sucks up the gas fumes from the tank and burns them.
http://www.hamtramck-historical.com/images/dealerships/SalesmansPocketGuides/1970/Pg 041.jpg