Samsung BHM1100NBACSTA - Manual (Page 8)

6
Charging the headset
This headset has a rechargeable internal battery which is non-removable. Ensure
that you fully charge the battery before using the headset for the first time.
1 Connect the charger to the headset (see below images).
2 Plug the charger in to the wall outlet.
During charging, the indicator light will turn red. If charging does not begin,
unplug the travel adapter and plug it in again.
3 When the headset is fully charged, the indicator light changes to blue. Unplug
the travel adapter from the power outlet and the headset.