Sennheiser NoiseGard HMEC 45-CA Instructions For Use Manual page 4

Switching the Active noise compensation on and off
Inserting the batteries
The ON/OFF switch for the power supply of the circuitry is located on
®
NoiseGard
the battery compartment. When power is switched on, a green LED lights up.
When the power supply is switched off or when the batteries go flat the headphone
works like an ordinary headphone without noise compensation.
As the microphone is connected to the aircraft´s internal power supply, it does not
depend on the batteries and will remain in operation should the batteries fail.
on/off
LED
Hygiene pads
(Accessories, not included in the scope of delivery)
Cat. No. 03553