If you remove the batteries will it you lose your zero?
No!
The battery compartment has nothing at all to do with the mount or the zero.
There is a cam lever on the top front of the sight.
Flip it up and the battery compartment slides forward off of the sight.
Dump the old battery's, slide two fresh ones in, slide the cover back on, and push the latch down.
Takes all of 30 seconds and you are back in business.
BTW: I also leave my battery's in all the time.
I treat them like a smoke detector battery.
Replace them on a set schedule, at least once a year, and they will not run down, leak, and corrode.
They will also be fresh & work when you hear a bump in the night!
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