Just a heads up... look closely at the base when you changes coils! There is a small clear o-ring on the bottom of the coil, occasionally it will come off and stick to the base! It is clear so when wet it is almost invisible, if you don't see it there and put on a new coil it wont seat right and you will get leakage out the air holes!! (Learned this when my Subox Mini and had the same problem!)