BE901-T/DSE901-T tank atomizer:for directly dropping e-liquid into 901-T tank system atomizer, only fits with 510-T and 901-T tank cartridge.
BE901-T/DSE901-T tank system atomizer:for directly dropping e-liquid into 901-T tank system atomizer, only fits with 510-T and 901-T tank cartridge (510-T and 901-T use the same tank cartridges).