This mask is having Dual connectivity model - GSM model where you can insert any SIM card to receive calls and talk with anyone and also Bluetooth mode where you can connect your phone via Bluetooth and use the mask to listen or Mp3 files or can also talk with anyone like a Bluetooth earphone system. 
In the complete set, you will get all the accessories like earpiece and earpiece cells ( each cell can work up to 4 hrs ), a Charging cable with an adapter and a user manual. 
you can get this in different colours like black, grey, and white.
This mask is having a battery backup of 4 to 5 hrs approx. 
 
In the box - 
1 MASK 
1 Earpiece 
2 cell ( 416 model)
1 charger and Adapter