I can second the motion about getting the compass away from other metallic items before attempting to use it. True story - I was in our new Dick's Sporting Goods checking out the camping and outdoor items, and a guy next to me was seeing if one of those small Brunton watchband compasses would fit on his watch. He told me he wanted to be better prepared in case of a terrorist attack. He was mildly put out when I suggested that he might want to put the compass on something other than his metal expansion wristwatch band - "Oh, will that make a difference?" he asked. Sigh ...