In reply to splat2million:
All silva compasses come with a 5 year warranty, my expedition 4 developed a bubble so I drove to the offices and swapped it for a new one there and then. Email/call silva and then will tell you if its within 5 years old. There is a backlog with warranty replacements so it may take a few week. The date for the compass is determined by the 2 small letters in between the red north arrow on the base plate.