Unique Magnetic Seal Allows Easy, One-Handed Vacuum Filtration of Liquids-No-leak magnetic seal allows one-hand operation. -Polyphenylsulfone construction is compatible with anti-foaming agents and many other solvents.-Convenient. 150 mL size allows for easy fit into small autoclaves and 500 mL size is ideal for filtration of large samples.-Sturdy and safe. Polyphenylsulfone construction provides durability and added safety at a cost less than most glass funnels.-Forceps access point allows easy filter retrieval.-Graduated at 50 mL increments for accurate sample measurement.-New 47 mm Sentino Magnetic Filter Funnels also available.-#8 stopper with proper bore hole size included This product is not approved for use in medical, clinical, surgical or other patient applications.