5V 2 Channel USB Relay Module Programmable Computer Control For Smart Home Arduino Description: This USB controlled relay board with 2 channels is used the HID technology， so there is no need to install any driver in windows system.It's convenient and very easy to use. If you need English file for this item， please write email to wangzhanxiemeijuan@banggood.cn or liwenping@banggood.cn or liujiahua@banggood.cn Specification: Relay type: 5V relay Contack type: NC \/ COM \/ NO Input current: !#!amp!*!ge;300mA Input voltage: DC 5V Support Win7， XP 32-bit systems Application: Robotics control Home automation Control doors and windows via windows system Controller power supply Package included: 1 x 2 channels USB relay