One-Button operation for easy sound adjustment
USB Rechargeable: saves on cost and energy with convenient charging
Double layer silicone earplugs: comfort during extended wear
10-second power-on delay preventing whistling and feedback upon start up
Digital display case: shows battery level for optimal monitoring
high capacity battery: Long lasting to keep you powdered throughout the day
Specifications:
Max OSPL90 (=123 3dB)
Frequency Range: 500Hz-7000Hz
working time: 24-28h
charging time: 2-3h
on/off: button
volume control: scroll whee