Plug Connection: 1.You can directly plug if you connect android phones, Apple phones, single-hole laptops and tablets 2.If you connect dual-hole desktop and notebook computers, please insert into the headphone output hole. In such state, only the headphones work and the Microphone has no function. Key parameters: Plug: 3.5 mm, straight peen, gold-plating Wire length: 1.2M Wire material: TPE Frequency Response: 20-20KHZ Impedance:16O 15 Sensitivity (dB): 95dB 3dB Speaker Diameter: F5mm Rated power: 2mW Maximum power: 3mW Package List: 1.A sleep headphone 2.A pair of black silicone ear wings 3.A pair of large, medium and small silica gel earcaps 4. Instruction 1Three-key toning wire control is adopted to adjust volume besides, three-key which can be pressed blindly is designed to improve the operability of headphones. During use, it is more convenient to increase and reduce volume. At the same time, it can be settled once to play, pause, last song, next song, answer, hang up as well as refuse to answer. Softer Silicone Ear Cap:After long-term use of headphones, in order to prevent headphones from falling off, we often add ear wings on the headphones. For this, we specially customized softer materials (silica gel hardness is 30 degrees however, the normal hardness is 55-60 degrees.) At the same time, we also spend much money to collect large amounts of ear models as well as develop the more suitable structure for ear contour. Fully Enclosed Acoustic Chamber: 5 mm voice horn custom-made by collation of totally enclosed acoustic chamber. In order to enhance the life of headphones, we specially customized a fully enclosed acoustic chamber. The smaller the speaker, the more complex the process at the same time the cost of production will increase geometrically. All of this is to create the more comfortable sound quality. Sound insulation:Significantly reduce the noise around even in the situations when you don't play music with the characteristics of sound insulation, noise reduction, as well as comfortable and compact wearing especially when playing music, you will enjoy your private time. Comfortable to Wear:The ear will not be coughed up to when lying on the side. You can freely turn over for many times with soft embedded ear wings and firmly-wearing.