Shenzhen Yishi Electronic Technology Development Co., Ltd. is a high technology company in security and wireless products field. We have a branch company in Taiwan area and a modern SMT plant in Mainland China, which has passed ISO9001 certification. Security and safety products, including various types of Standalone DVR, CCD Cameras, IP cameras, NVR and Telephone recording products. D Wireless products includes Data Radio, FSK RF modules, ASK transmitter and receivers in wireless ...