If you have a fire you can never have too many fire extinguishers. Nothing worse than thinking you have put the fire out then it reignites with no extinguishers left. Its a long time before the red flashing lights turn up and you run out of marshmallows as well. Some are one shot once trigger pulled you need to refill and the bigger ones you can squirt a little bit then put away until your next mishap. We get all ours serviced annually.