@Pink Warrior
I might be misunderstanding you, but just in case I am not…here is some info (please forgive if you already know all this – I am only trying to help).
At the top, the only place that opens is where you put the batteries – and it sounds like you already found those arrows and inserted the batteries. The round disc on the very top is to be pressed down so the salt/pepper comes out and the light goes on. It does not open, just press.
Near the bottom ¼ of the mill, at the top of the clear plastic part, you will find two arrows on the plastic and one arrow on the metal. That is where you turn it to add the salt/pepper. You can buy the really coarse salt at the grocery store – Morton’s sells a clear jar with a black top that is specifically for refilling salt mill/grinders.
Hope this helps. We LOVE these mills – I had a set and we bought 2 more sets when they were the special right before Christmas. I do have to say some comes out the bottom, so I keep mine on a small saucer on top of the stove.
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