If you're talking about the one at the end of the board, it looks like either an inductor (see the response in one of the other threads by this same name) or coil antenna. They're encased in hot glue or silicone to make them a little more robust and give a little bit of environmental protection (depending on what you want to use them for).
Looks like an inductor but a low value one. You can see the wire coil(?). Is there a screw adjuster in the centre of the cylinder? Is there a "H" printed on it to show its inductance or is there an "L" printed on the board, like the Rs and Cs? It looks like a small inductance which is odd, considering the surrounding components and their layout, which suggests lowish frequency of operation. It could be a transformer - how many connections are there? IS there a "T" on the board?
MATLAB's suggestion is also possible.
Does the board work? What does it do?
There are more questions than answers, I'm afraid but I hope they help.