You may want to check with your local fire department. I don't know what their policies are on refilling bottles that weren't used at a fire they responded to. I do know that when I had just got my extinguisher from a buddy, the last time it was checked was in 1989, so I think it might have been the Halon stuff, but I don't know what it is, I had only had it for a day. There was a car fire in the parking lot across from my dorm, and since it was sitting in my room, I grabbed it and ran across the street and tried putting it out. It kept it down enough till they could get there, but they recharged it for me for free. So long story short, check with your local fire department. P.S. I accidentaly inhaled some of the chemicals in it and it made me cough really bad for about a day, does this mean it was the Halon stuff? Hope this helps, Christian