Wireless Hearing Amplifier AMPSound – Personal Sound Amplifier for TV Listening – Rechargeable Bluetooth Hearing-Aid Like Audio Stereo Amplifier with Charging Case – Sweatproof Earbuds - Hunting Gear SuperStore
Why don't you just change it early? <--there are exceptions (i., accidentally left one on overnight) and batteries are expensive! I am so glad mine just go "*DOO!" which is a shorter heart attack than hearing "BATTERY"