A flow indicator of a breathing apparatus that indicates a flow of a breathing-gas includes a structure within a conduit for delivering the breathable gas, where the structure undergoes a change as a result of a presence of the breathable gas or a movement of the breathable gas past the structure. The flow indicator also includes a gas flow display that is actuated by the change in the structure to visually indicate a presence or flow of the breathable gas, where the display is powered by the change in the structure without any outside power supply.
