The Stealth Secret Sound Amplifier is the revolutionary sound amplification system that is affordable and discreet. The soft foam handle fits over your ear. The Stealth S.S.A. comes with 3 sizes of soft tips allowing it to be worn in both left and right ears. This product includes rechargeable batteries as well as a charger. Always charge your amplifier for a minimum of 4 hours prior to first use for the best battery power over the life of your unit. When the red light goes off, the battery is fully charged. The Stealth S.S.A. will hold a charge for up to 10 hours if the initial charging instructions are followed properly. Audio feedback may be caused when the Stealth S.S.A. earpiece is exposed to its own super-sensitive microphone. This usually results in a high pitched noise. If this happens please remember to switch the unit to OFF before placing/removing it from your ear.