Bell in a vacuum
Inside a closed glass jar by the gradual depletion of air, ringer sound fades, and finally die down.
On the plastic base, a bell pump is placed. Under this bell, an electric ringer is placed. Sound is the vibration of air or other media. In a vacuum, sound vibration does not travel, because there is nothing that can oscillate.
Material: glass, plastic, wood
Power supply: 220 V
Dimensions (cm): 60 x 40 x 40