Hi,This is Jackie Shen from Ningbo BTL Audio who is a professional supplier on providing & designing compression driver, woofer, voice diaphragm, and other speaker components. Our factory in Ningbo has 25-30 workers, 2 engineers, and around 3000M2 workshop area. We have stood in this field for more than 14 years. We not only produce by ourselves but also cooperate with other manufacturers to provide customers more choices. Now we have cooperators from all around the world, including Russia, South Africa, India, France, Poland, Bulgaria, Panama, Germany, Denmark, USA etc.. If you are interested in any products of BTL, please kindly let me know. We will do our best,let's work together!Learn more about us, please visit our website: www.btlaudio.com.Best RegardsJackie Shen