Bunkers above Pok Fu Lam Reservoir [????- ]
If you look carefully you can see it as you take the steps down from the service reservoir to the main reservoir. It's about one third of the way down the steps, on the left. It has the wavy outline along the top of the concrete that we have seen on other, similar bunkers.
At the bottom of the steps, if you turn left you'll soon come to a small stream and a public toilet. There are several more bunkers here, both at road level, and further up the slope. This bunker is likely part of that same group, so it will be worth a more careful look around this area later.