Features: This extremely portable, lightweight wireless audio transmitter & receiver is an ideal wireless audio solution for a wide range of situations and uses Transmitter mode:wir elessly streams audio from your non-Bluetooth -compatible TV, home stereo system, or CD player to your Bluetooth -compatible headphones or speakers Receiver mode: wirelessly streams audio from your Bluetooth -compatible -enabled phone, tablet, or computer to your wired stereo, speakers, or headphones Switch between transmitter and receiver modes with the simple flick of a switch. Effortlessly connect using advanced Bluetooth -compatible technology and 3.5mm audio cabl. Super-Portable Audio-Streaming Power The KN319 is just 44mm (1.73") across and weighs only 18g (0.63oz), but has got powerful wireless audio streaming capabilities. Slip this transmitter & receiver into your backpack or laptop bag and take it on-the-go without the slightest effort. Broad Compatibility: With the included 3.5mm cable and 3.5mm to 2RCA cable, this Receiver Transmitter adapter can widely be used on your computer, laptop, home stereo system, headphone, smartphone, Mp3 player, CD player, etc. Specifications: Model: KN319 Technologies: BT4.2, A2DP, AVRCP (receiver mode only) Operation Range: Up to 10m / 33ft (without any blocking objects) Charging Time: 2 hours Continuous Use Time: 6 hours (Receiver Mode) / 5 hours (Transmitter Mode) Battery Type: Li-Polymer (200mAh) Dimensions: 44 44 12mm Weight: 18g Note: Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you Please allow 1-2cm measuring deviation due to manual measurement. Package Included: 1 x Bluetooth Audio Transmitter/Receiver Adapter 1 x User Manual NO Retail box,Packed safely in bubble bag.