Probe positioning device for a flask freeze drying

A device for positioning a probe in a flask for freeze drying, said device comprising:

• a stopper adapted to be secured to an open end of said flask defined at a neck of the flask, said stopper having a center opening and multiple radial openings spaced from said center opening, each radial opening being disposed at a common radius from said center opening, wherein said multiple radial openings comprise an annular-shaped passageway for fluid communication between inside and outside of the flask when the stopper is secured to the open end of the flask, said stopper comprising a disc-shaped member and a cylindrical member depending therefrom sized to reside within an inner diameter of the neck of the flask, each radial opening comprising an arcuate-shaped opening in said disc-shaped member and a corresponding channel formed in an outer circumference of said cylindrical member;
• and
• a guide tube held within said center opening and extending into the flask when the stopper is secured to the open end of the flask, said guide tube being sized to receive the probe and allow the probe to extend from the guide tube into the flask, wherein said center opening with the guide tube and probe held therein allows substantially no fluid communication between the inside of the flask and the outside of the flask when the stopper is secured to the open end of the flask.