I've seen this question a dozen times but can't find it now, of course. My Danforth compass has lost some fluid. I don't use the compass really, but it looks bad. The dome/ball pops out of the mounted base leaving the base/bracket and light still mounted. There is a rubber plug the size of a quarter on the bottom, but I can't figure out how to remove and refill. I also can't find a source to buy just the dome part to replace it (easier than removing the bracket and wires, etc.) Rule does not show this model on their website. I have no manual and the compass is only 5 years old.