Features 1、Supports for Raspberry Pi A + / B + / 2B / 3B. High quality relay, loads up to 250VAC / 5A, 30VDC / 5A. 2、Photo link isolation, prevent interference from high voltage circuit. 3、Onboard LEDs for indicating relay status. 4、Relay control jumper, ensures to the relays by custom pins other than the standard pins. 5、Comes with development means, including examples in wiringPi, WebioPi, shell, python, and bcm2835. Specification Description: RPi Relay Boards Enable Pi to Control High-Voltage and High-Current Devices and Make Common Domestic Appliances Smarter. Supports for Raspberry Pi A + / B + / 2B / 3B. High quality relay, loads up to 250VAC / 5A, 30VDC / 5A. Features: RPi Relay Boards Enable Pi to Control High-Voltage and High-Current Devices and Make Common Domestic Appliances Smarter. Supports for Raspberry Pi A + / B + / 2B / 3B. High quality relay, loads up to 250VAC / 5A, 30VDC / 5A. Onboard LEDs for indicating relay status. Photo link isolation, prevent interference from high voltage circuit. Relay control jumper, ensures to the relays by custom pins other than the standard pins. Comes with development means, including examples in wiringPi, WebioPi, shell, python, and bcm2835. Specification: Condiiton: 100% Brand New Raspberry Pi GPIO interface: For connecting Raspberry Pi Relay screw terminal: For connecting target devices Relay indicator: LED on: relay NC is open, NO is closed LED off: relay NC is closed, NO is open Power indicator Relay control jumper: short the jumper: control the relay by standard I / Os used in the example code open the jumper: control the relay by custom I / Os via jumper wires Terminal Description: 1. The expansion board has four terminals, each terminal has three pins for connecting external circuits Package Included: 1 x Expansion Module for Raspberry Pi Notice: Please allow 1-3cm error due to manual measurement and make sure you do not mind before ordering. Please understand that colors may exist chromatic aberration as the different placement of pictures.