Siemens plug in circuit breakers are intended for use in Siemens EQ, Siemens Ultimate, ITE, and Gould load centers or meter combinations. The double pole Siemens breakers may be used in single or 3-phase load centers and are 240V rated. To ensure the warranty on a Siemens panel is not voided, the use of Siemens breakers is required. The QN2200 is intended for use in applications in which the breaker is mounted vertically, common in some meter main combination panels.