Fitting range: hearing lo 70dB Peak gain: 114 dBSP Saturated sound output: 1024 dBSPL Battery life: about 15 hours for hearing aids Charging box: can charge the hearing aid 12 times (6 pairs) Charging time: 4 hours Features: It is a cost-effective open-behind-the-ear hearing aid product. It is invisible, comfortable and breathable to wear. The multi-channel croover noise reduction of up to 9dB makes listening clearer and quieter. Two multi-function buttons, adjustable volume and program switching, pre-made three A listening program (universal, crisp, thick), easy to switch, cycle rechargeable design, solve the worries of buying a battery, and have a volume/program memory function, which can avoid the inconvenience of each startup and debugging proce.