Octopus 1 Channel Relay 3V Relay Module is one of the OCTOPUS series of electric bricks. It is fundamentally designed according to OCTOPUS electric brick series with the same shape, PCB positioning holes, and electric brick connectors. OCTOPUS 1 Channel Relay has adopted a mini and high-quality HUIKE relay, which is available to control all kinds of home appliances and high current load devices. This is a common accessory module for electronic DIY fans.