Norcold AC Heater/ Heating Element 638374 (fits the Polar N7/ N8/ N10/ and newer N6XX/ N8XX models) This AC heater/ heating element replaces the Norcold 630811. This is the AC heating element that works on the following models: N7 NA7 N8 NA8 N10 NA10 All N611, N621, N641, N811, N821, N841 models man... See More