This panel is designed to meet EUSERC requirements. Included in this panel is a 400 amp rated, test block bypass meter socket. The interior includes a factory installed 200 amp main breaker that feeds an 8 space, 16 circuit interior with feed thru lugs. There is also a provision for an additional main breaker up to 200 amps. The additional main breaker can vary from 15 to 200 amps using the QP and QNR types of breakers. Utility acceptance for all metering products varies, so check your local utility for acceptance prior to installing.