Sending 0x55 out Serial Port

I have a few US-100 serial ultrasonic distance sensors, I think I understand how to get data from the sensor, but before I do that I need to send 0x55 out that port.

My item for reading the sensor is:

String Hydrogen_Peroxide_Sensor {serial="/dev/ttyUSB1@9600,BASE64"}

    sendCommand(Hydrogen_Peroxide_Sensor, '\u0055')