Cat on cat aggression, help?!?

This is a territorial thing that is very common in cats, especially females. It is partially a gender thing, mostly a territorial thing and this is when cats tend to fight, and even neutered males tend to spray urine on walls, furniture. This all causes stress which leads to aggression. This happened to me , and I bought a plug-in at a petstore from a brand called 'Comfort Zone' that I plugged into an outlet. The cats have been calm since; it releases feline pheromones 24hrs a day that calms a cats nerves. The refill lasts about a month to a month and a half. It's definitely worth buying, the only thing that has worked for my two male cats in a one bedroom apt.