Surface activated growth area for optimal adhesion and best proliferation of adherent cells Suitable for suspension cells Geometry of the neck reduces risk of media slop over Stabilizing rim offers secure, slip free piling of several flasks Highly visible bilateral marking area White volume graduations on both sides for optic control of the filling volume Crystal clear transparency Flasks are available with «VENT» or filter screw caps Filter screw caps offer constant sterile gas exchange through the hydrophobic non-wetting PTFE membrane with pore size 0.22 μm The opto-mechanically treated/activated growth area enhances optimal cell adhesion and best proliferation. The geometry of the neck guarantees total access of TPP pipettes, TPP scrappers and the TPP spatula. No dead corners = 100 % cell retrieval.