The Schneider Electric ZD4PA22 is a 4-pole auxiliary contact block and is used to provide additional switching in addition to the main contacts of a circuit breaker. It provides an additional contact pair, two normally open and two normally closed contacts, which can be used to control other circuits, or to be monitored around the circuit breaker. It has a 1 NO + 1 NC contact configuration, and is designed for use with 4-pole circuit breakers.