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How to fix circular light bulb?
(aussie.zone)
So, there's the circular bulb itself, and also this little removable plastic cylinder with two metal feet on it. How do I tell which of them needs replacing, and what specification to look for to know what to replace it with?
Dark spots means the tube is worn out and could definitely use replacing even if it did still work.
You might consider removing the whole thing and putting in an LED light instead.