The 2.5 lb Halotron I stored pressure fire extinguisher is a "clean agent" fire extinguisher, meaning it is residue-free. It is also earth-friendly. Extremely low in both ozone depletion and global warming potential, this extinguisher is an excellent replacement for halon 1211 extinguishers. Ideal for use on computers, telephone switch rooms, electronic data storage equipment, basically anywhere you have sensitive electronic equipment.