Hi all! Newbie here and couldn't really find what I needed using the Search.

Recently purchased a used 2007 Aspen with NAV and no disc. In trying to find one online and eBay, we are finding a lot of different numbers ending in 'A*'. I know that we have a REC unit, but does it matter what 'A*' number disc we get? Do they increment up as newer ones are released?

Thanks in advance and sorry if this was covered somewhere and I missed it!