The vortex valve is a designed to demonstrate the how a tornado swirls. Connects two large soft drink bottles. When one is half filled with water, with a flick of the wrist a tornado in a bottle is created.

Scientific fun. Now supplied with two '0-ring' seals to protect against leakage.

• Connects two large soft drink bottles.
• When one is half filled with water, with a flick of the wrist a tornado in a bottle is created.
• Scientific fun.
• Now supplied with two 'o-ring' seals to protect against leakage.