Item Type: Hearing Aids Amplifier Working Current: 1.2mA Signal to Noise Ration: ≤32dB Max Out: 129 ± 3dB Max Gain: ≥ 40 ± 5dB Harmonic Distortion: ≤10% Colour: Silver/ Light Blue Features: 1. Safe charging , Long standby time 2. Digital chip, Intelligent noise reduction 3. Anti-howling, Easy Operation Volume Control 4. Bendable Earline 5. Lightweight 6. Fully charged replaceable artery can stand up to 40h use. Package Included: 1 X Principal machine 4 X Earplugs 1 X Cleaning sweeper 1 X USB cable