Typically, a fire extinguisher consists of a hand-held cylindrical pressure vessel containing an agent which can be discharged to extinguish a fire. In the United States, fire extinguishers in all buildings other than houses are generally required to be serviced and inspected by a Fire Protection service company at least annually. Some jurisdictions require more frequent service for fire extinguishers. The servicer places a tag on the extinguisher to indicate the type of service performed (annual inspection, recharge, and new fire extinguisher).