I decided to take on the Drip On Demand, from madvapes. The DoD is described as:
An automated vacuum driven e-liquid feed system for use with 510/901/808 atomizers and cartomizers. The screw in bottle is easily accessed to squeeze for a little extra boost whenever you require more e-liquid. The DoD is simple, reliable and inexpensive.
An automated vacuum driven e-liquid feed system for use with 510/901/808 atomizers and cartomizers. The screw in bottle is easily accessed to squeeze for a little extra boost whenever you require more e-liquid. The DoD is simple, reliable and inexpensive.