Square D Tandem Circuit Breakers QOT1515, 1520A, 120V AC

A tandem breaker fits two individual breakers into the size of one That allows you to add new breakers when your breaker box doesn't have any new slots

slot This key will unlock a series of other key slots , each containing one breakers so that they cannot be opened until after the oil circuit breaker

two slot shelving There must be an open slot in your electrical panel to add an additional breaker Otherwise, you may need to upgrade your panel or add a second

two breakers in one slot What he said is correct That is 2 circuits that take up one breaker slot Each circuit requires its own neutral Something you need to look