QO and QOB one, two and three pole thermal magnetic circuit breakers provide overcurrent protection and switching on ac and dc systems. These circuit breakers have an over center, trip free toggle mechanism with quick make, quick break action and positive handle indication. They also have VisiTrip trip indication, which provides a visual indication that the circuit breaker has tripped and interrupted the circuit. This 2 pole QO standard plug on circuit breaker with common trip is rated as 50 A, 120/240 VAC. This unit provides 10 kA breaking capacity. This circuit breaker has a HACR rating. A full line of factory installed accessories, such as shunt trips, auxiliary switches and alarm switches, is also available QO breakers use a compact 3/4 inch width design for small system footprint. QO circuit breakers are UL Listed under UL File E84967 and are CSA Certified under CSA Master Contract 153555