The Sound Trap uses four AAA batteries, two in each cup. To change the batteries, follow the steps below:
1. Power off the Sound Trap,
2. Reach into the inside rim of the ear-cushion ( ring ) and pull straight out,
3. Remove the gray foam insert, be careful not to damage the electronics,
4. Now the batteries should be exposed: remove them carefully,
5. Install fresh batteries, make sure polarity is correct,
6. Replace gray foam insert and snap back the ear cushion, ensuring a tight fit,
7. Repeat the same procedure for the other cup,
8. Turn power on to check working conditions.