Colorful 2.4g wireless earphones features: 1.Chatting online; 2.Transmission range:larger than 10m; 3.Sound:full acoustic fidelity and strong bass voice; 4.Invisible noise reduction mic inside guarantees acoustic fidelity; 5.Battery:180 hours long standby/lithium battery inside lasts for 8 hours; 6.Intelligence code system:share music online with friedns with one emitter. Detailed specifications: 1.Frequency range(ghz): 2.404~2.476. 2.Avaiable range(m): 10.. 3.Baud rate(bps): typ:4m.. 4.Successive working time: about 8hours. 5.Battery: chargeable lithium-ion polymer battery (3.7v/320ma/h)... Two part:...Speaker parameter: 1.Speaker diameter: 40mm.. 2.Impedance: 32 3.S.P.L: 118db s.P.L.At 1khz.. 4.Rated power:20mw...... 5.Aggregate capability:40mw.. 6.Frequency response:20hz-20, 000hz Microphone parameter. 1.Microphone unit: 4*1.5mm.. 2.Directivity:omnidirectional. 3.S.P.L:-58 4.Impedance: 5.Frequancy response:30hz-16, 000hz.. 6.Operating voltage:3.0v. Blister and papercard