Hot answers tagged alarm
My suggestion is that you try pressing in (or up) on these two tabs: And then that the lower part of the unit will hinge down. The hinge edge being along here:
HEMS, the vendor, answered my enquiry. There is actually a clip (first image in the original question) with an arrow mark on it. The problem is that the mark is uncoloured, very difficult to be noticed from where I stand. Push the clip to the left to release the lock, then pull down the whole thing.
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