There is a drain port at the bottom of the culture bottle for sterile liquid preparation; it is used with a sterile Filling Bell. The bottom has a 1/2inch hose connector for sterile dispensing.
WHEATON 3910-07 Culture Flasks, Suspension Culture, With Screw Caps, Shinetek Instruments Research Institute (CAT#-STEM-CC-3430-LGZ) WHEATON 3906-13 Culture Flask, Media Storage and Dispensing, with Bottom Drain, Shinetek Instruments Research Institute (CAT#-STEM-CC-3425-LGZ) WHEATON 3908-20 Culture Flask, Suspension Culture, Without Lid, Shinetek Instruments Research Institute (CAT#-STEM-CC-3426-LGZ) WHEATON 3908-24 Culture Flask, Suspension Culture, Without Lid, Shinetek Instruments Research Institute (CAT#-STEM-CC-3427-LGZ) WHEATON 3910-03 Culture Flasks, Suspension Culture, With Screw Caps, Shinetek Instruments Research Institute (CAT#-STEM-CC-3428-LGZ) WHEATON 3910-05 Culture Flasks, Suspension Culture, With Screw Caps, Shinetek Instruments Research Institute (CAT#-STEM-CC-3429-LGZ)