Koolulu Bluetooth Premium Headset, Black PRODUCT DESCRIPTION  Over-ear style  Inline mic  Ear cups fit around ears to help isolate audio  Also works great for DJ monitoring and recreational listening  Equalizer for switching between genres  MicroSD card plug-in  Extended frequency range  Deep, accurate bass response  Matte finish design  5-button control: Play/Pause/Answer/Hangup; Equalizer for switching between genres; Next Track/Volume Up; Previous Track/ Volume Down; and Mode to switch between Bluetooth, FM radio Music Play  On and Off switch  Can also play music with a 3.5mm aux jack  Bluetooth: 4.1  Battery: 3.7V 250mAh  Frequency: 20Hz-20KHz  Working distance: 30'  Play time: 6 hours  Standby time: 300 hours  Charge time: 2 hours  Drive unit: 32? 40mm  Measures 7" L x 7" W x 1" H  Weighs 5oz *This product is a multifunction player which gathers the functions of loud speaker,headset,battery charging,Bluetooth. *Use high-power power amplifier chip and advanced circuit design *Use strong magnetic ,full frequency loud speaker,sound effect is much more loud and clear *With high capacity and safety battery,working life can be as long as 3 years *The Bluetooth can be automatic connected when pairing second time *When the battery is empty,the product can still use connect line to be used as a normal headset