MS16A / MS14A IR sensors CM13U ... X10

I have the above movements sensors and a CM13U, I live in the UK.

My question is ... Am I correct in thinking that the sensors are US standard and the Receiver is UK standard and therefore they transmit and receive different frequencies?

I know I may be answering my own question but I want confirmation. I assume the A on the end fo teh MS14A stands for USA? As you may be able to tell, I'm new to this :)

Thanks for your help.

Lee.