Hearing Amplifier, Audio/Sound Amplifier with Rechargeable Battery Hearing Amplifier Convenient & Comfortable Wireless Design Effectively Reduces Background Noise Tested to Provide a More Comfortable Listening Experience ASC (Automatic Signal Control) Regulates & Balances Sound - Amplify Sounds up to 30x - Built-in Rechargeable Battery Comfortable Non-Interfering Design Made to Fit: For Ears All Shapes & Sizes - Easily Adjustable Volume Control Wheel Includes Changeable Earbuds / Inserts (Small, Medium, Large) Charging Power Adapter and Docking Station - Also Included Long Lasting Battery Life: Lasts up to 12 Hours Simple ON/OFF Switch Technical Specs: Battery: Rechargeable Lithium-ion (1.2V) - Working Current: &lt;3mA - Signal to Noise Ratio: &lt;28dB - Frequency Response: 100-400Hz - Audio Gain: 30dB - Distortion: &lt;6% - AC Power Adapter: 100/240 Volt - Battery: 1.2V Sold as: 1 Weight: 0.39 lbs.