How to open this?

[Scatterling]

Please tell me how to open this fitting to change the bulb.

[Reefmagnet]

Push the lens and rotate counter clockwise

[dksail]

If the lens doesn't come off as per Reefmagnet, carefully rotate the entire unit.

[Island Time O25]

It may just be a shadow but it seems like a notch for a flat screwdriver tip at 7 o'clock.

[Scatterling]

Originally Posted by Reefmagnet

Push the lens and rotate counter clockwise

Thanks! Easier said than done as with most boat things, but I got them off. I added a bit of silicone grease to facilitate removal in the future.