Is a retaining kit required when installing a QO breaker in a QO2100BNRB?
Circuit Breaker Enclosure
No, it would not be required. A retaining kit is required when backfeeding a branch circuit breaker to provide power to a panelboards bussbars. The QO2100BNRB is a circuit breaker enclosure and the QO breaker is not being backfed.