The RPi Relay Board gives your Pi the ability to control high voltage/high current devices, easily makes normal become intelligent. RPi Relay Board Features Standard FOR 40PIN GPIO extension header, supports series boards relays, loads up to 5A 250V AC or 5A 30V DC Photo coupling isolation, prevent interference from high voltage circuit Color: blue, black Material: PCB Onboard for indicating relays status Relay control jumper, allows to control the relays by custom pins other than the default pins What's on the RPi Relay Board FOR GPIO interface:for connecting Relay screw terminal:for connecting target devices Relays Photocoupler:PC817 Relay indicator LED on: relay NC is opened, NO is closed LED off: relay NC is closed, NO is opened Power indicator Relay control jumper short the jumper: control the relays by default I/Os used in the example code open the jumper: control the relays by custom I/Os through jumper wires Package Contents: 1 x RPi Relay Board 1 x RPi screws pack Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.