What dimension downstem does a q vaporizer with fashionable equipment hook to on a bong? I'm looking to attach my bong to my excessive Q tower 4. 0 vape, but I suppose the downstem might be too small as it wont fit in, does anyone know what dimension the vapes ends are so I can purchase a brand new sized downstem for the bong? Answer via BEERIs this a marijuana related question. [? ] Thought so.