Just a quick observation about compasses in the $20 range. . I had purchased several Suunto compasses back in the late 90's for use in geocaching. For at least the last 12 to 15 years they have been setting in gear bags in my closet.
Recently pulled them out and looked at them. . EVERY ONE had developed a significant bubble and for all intents and purposes was not real useful.
I realize you can't expect much, BUT I still have a Boy Scout compass that I purchased in 1965. It has NO bubble and is still usable.
Sad commentary!
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WesleyH