Use The Speakers - Nokia Md-6 User Guide

ENGLISH
insert the catches on the cover into the corresponding slots on the
speakers, and carefully slide the cover toward the speaker elements.
To remove the batteries, open the battery cover, and pull the ribbon to lift
the batteries from the compartment.
During long periods where the speakers are not used, remove the batteries
to prevent damage from battery leakage. When battery power is low, the
orange indicator light flashes.

Use the speakers

Slide the release switch of the speaker cable toward the audio plug, and
uncoil the speaker cable.
To connect the speakers to a compatible Nokia device that has the Nokia
3.5 mm AV connector, insert the audio plug into the connector on your
device.