Capsule type bar protector - has ventilation ports delivering air on change in internal volume

摘要

The ear protector has capsules with elastic distorting seals. At least one ventilation port (1) is provided in each capsule (3), and the air inside is changed by altering the internal volume. There can be two ports, one with a suction and one with a discharge valve, the former having an air guide tube (2) leading to the capsule interior, and running in a labyrinth pattern. A pump can be provided to alter the volume.