Originally Posted by N941WR
My first two panels had back up airspeed and altimeters fron Van's. By the time I got to panel #3, I removed them and never looked back.
If you really want a backup, get a Dynon PocketPanel. Its battery will last around four hours and it doesn't tie into your pitot or static lines. Granted it gives you ground speed and not airspeed but that is better than nothing should your pitot or static lines get plugged.
Still have them? Want to sell them?