For use on a pump plate of not less than 15 cm diameter. An electric bell operating on 4–6 V AC/DC is suspended on an elastic cord inside a bell jar. Fine looped-wire connections run to terminals mounted in an elastic bung that seals the jar.

We are manufacturers and suppliers of the Buzzer In Vacuum apparatus, exporting to Algeria, Argentina, Australia, Bahrain, Bangladesh, Belgium, Bhutan, Brazil, Cambodia, Cuba, Cyprus, Denmark, Ecuador, Egypt, Ethiopia, Finland, France, Georgia, Germany, Ghana, Hungary, Iceland, Italy, Japan, Jordan, Kenya, Kuwait, Malaysia, the Philippines, Tanzania and Uganda.