Question: are first alert and kidde compatible?
Answer: First Alert ADK-12 BRK/Kidde Smoke Alarm Adapter Plugs This product is compatible with BRK and Kidde Smoke Alarms and saves time and installation costs when retrofitting existing homes or apartments. Compatible BRK alarms: 4120-series, 9120-series, 7010-series, 5919,2002RAC, SC6120B, SC9120B, HD6135FB, RM3.