Ahh.. the two cross-drill holes.
By theory, the threads of the battery are relieved in that area (just like on the atomizer of a 510) and that creates an air galley. So it shouldn't be necessary to rotate the notches to line up with the holes. If it makes a difference on your unit, I'm wondering if the galley (thread relief) wasn't cut.. or wasn't cut deep enough. Might also explain why some are harder than others to screw on all the way.
<ponder>
By theory, the threads of the battery are relieved in that area (just like on the atomizer of a 510) and that creates an air galley. So it shouldn't be necessary to rotate the notches to line up with the holes. If it makes a difference on your unit, I'm wondering if the galley (thread relief) wasn't cut.. or wasn't cut deep enough. Might also explain why some are harder than others to screw on all the way.
<ponder>