Shenzhen Sigma C&T CO.,LTD is specialized in computer soft system and communication part, we have coperated with serveral companies like IBM, Sony , Philp, CSR. and our communication product is for bluetooth series, bluetooth headset, dongle, handfree car kit. and also we can operate mang other items, such as mobile phone accessory, mp3, bluetooth / mp3 glasses, usb flash driver, usb mobile charger, usb coffie heater , car dvd etc.