Hello @wkearney99 I don't see 4-Relay module in UIFlow (yet). No, I don't think you can use the UIFlow for 4-Relay unit since the I2C registers are different. 4-Relay module uses register 0x10 to control the relay vs. 4-Relay unit uses register 0x11 to control the relay and LED (register 0x10 is a control register). Documentation for 4-Relay module. Documentation for 4-Relay unit. BTW: you could use the default I2C Master blocks (under Hardwares) to control the 4-Relay module. Thanks Felix