Bass Fishing Forum - Westernbass.com

I currently have 2 elite7ti unit on my boat. I have updated my console unit wirelessly and all is good. My question is, can I update my bow unit with the same SIM card? Or do I need a separate card.? Do I even need a card installed my bow unit at all? The SIM card in my console unit has my navionics maps on it.
Any advice would be appropriated

An update downloaded from the Lowrance web site for a certain model should work in all units of that model.