The AIRPAX / SENSATA 279-2-1REC4-53F-9-8-5 is a hydraulic magnetic circuit protector within the 209 series. This circuit breaker combines power switching with accurate, reliable circuit protection in a compact single or multi-pole unit, making it ideal for branch circuit applications such as EDP, air conditioners, panel boards, and lighting controls. Utilizing the hydraulic-magnetic principle, the 209 family adapts to local applications and environments, minimizing nuisance tripping due to temperature variations. It withstands high pulses without tripping, ensuring consistent protection.