More efficient oil absorption from your vape cartridges, the upgraded A3-C Vaporizer Cartridge does the trick nicely by adding an extra inlet hole for a total of five. Each inlet hole features a precision angled cut to help with oil flow so the ceramic wick absorbs it more efficiently. This model also features a thinner center post so the filling tasks have never been easier or simpler. The ceramic wick allows for flavorful draws that allow you to really savor your waxes, oils and concentrates. Cartridges feature a filling hole size of 1.6 mm and a 1 ml capacity.