Botzees
Keyestudio
Fischertechnik
HarBottle
Harbottle helps students understand the meaning of fluid pressure and pressure reduction.
A Harbottle is a spherical glass container with a balloon stretched over its opening and a hole in the flattened base that is fitted with a rubber stopper.
Students are amazed when the balloon remains inflated inside the bottle even though it is not tied off or sealed.
