FIDELITY&reg; Bluetooth Speaker Mini Portable Speaker Powerful Loud and Clear Sound with Bass / Built In Micro SD Card reader / Built in Mic For Phone Calls / Works With All iPhones / iPhone 5c And 5s / All iPad's / iPad Air And iPad Mini Retina / iTouch and iPod / Nexus / Samsung Galaxy Note And Tab / Samsung Galaxy S4 S3 S2 / And All Phones and MP3 Players. Speaker System Has Replaceable Rechargeable Battery Includes USB Charging Cable and 3.5mm Cable to connect your device to the speaker. Features loud volume range with bass feature. Frequency Response: 60Hz-18KHz. Has a slot for SD cards. Includes a Built in Mic which allows you to use the speaker for phone calls as well. Removable 500MAH battery with 5 hour battery life. There might be a low and subtle steady noise coming out of the speaker, This is a electromagnetic-acoustic sound from the speaker, This is normal with most speakers, just press the "play/pause " button, this will mute the noise.