I bought the ROKU 55r615 in the USA and will now be moving to South Africa.
The power there is 220 VAC and 50 HZ.
Most electronics these days work at 110 VAC or 220 VAC.
I cannot see anything on the documentation to clarify.
Look on the back of the TV and it may say. My several years old TCL RokuTV states 120V, 60Hz.