I got my real 510 connectors with an airhole from Nerf today (thanks again), popped the passthrough connector off and put one on, connected up a Nebula battery and it worked ok but there was too much airflow resulting in much sucking to activate the switch and juice in mouth which I never get with 510's normally. I've temporarily put some tape around the join, not pretty but it works perfectly now, I have a lot of nebula batterys and passthrough and prefer 510's/dripping to cartomizers and the adaptor provides a buffer for excess juice so it should never drip into the battery.