The inside surface treatment by TPP provides an optimal growth surface on the flask base for the most varied matrix-dependent tissue cultures. The untreated side and top inside surfaces reduce the amount of cell loss during the separation phases because undesired tissue adhesion outside the growth zone is diminished. The flasks innovative shape is of such a design that devices inserted through the flasks neck have optimal access to the entire base surface. This means that there are no dead corners that cannot be reached with pipettes or cell scrapers.This excellent accessibility is due to the large neck opening and the favorable angle of inclination. The angled neck also reduces the chance of accidental spills and permits dribble-free pouring.When the vented screw cap is tightened to the end position the closed tissue culture flask is liquid and gas tight. By simply unscrewing the cap one quarter of a turn the flask is in the VENT position with the inside of the flask being aerated