Arjen:

Thanks for the explanation. Right now I have an X10 plug-in remote (i.e. that's plugged into the A/C outlet). The remote has 5 buttons, as well as a switch that switches codes from 1-5 and 6-10. Each button correspond to a single control of a device. For example, 1 is for pool light, 2 for spa light, 3 for backyard light......7 for pool heater, etc. So with this setup should I get the IR543 or the IR543AH? Also, where can I buy this and would you know how much?

Thanks again...........Joe.