Even though the maker's docs specifically say it is made for controlling ceiling fans, don't bother. I ended up with more than a simple hum noise. I was way too loud to even consider using this. In fairness the docs do say it can hum but the only way to know is to actually test. My test was awful. Connected to the wall for no more than 1 minute. Also, the switch paddle mechanism is so flimsy, you have to wonder if the rest of the unit is as poorly built. I own a fair amount of X10 stuff and this is certainly not up to snuff. The seller seems great so far - approved a return and it is still in shipment back.
Works as advertised.
Your switch box must have a neutral wire !
Most hardware store LEDs will only dim to about 30% of full bright.
Seoul Semi Acrich2 LED modules dim down to say 5% of full bright.
This item is not suitable for most LED lighting circuits, as they would have to total over 60 watts for the switch to work properly. It also fails to turn LEDs off completely, similar to X-10 lamp modules. The item is labeled "Pro", but construction and performance is not comparable to other manufacturers X-10 Pro switches, such as Leviton. They were capable of properly switching any LED load, and were well constructed with screw terminals instead of wire leads, but are no longer available.
I purchased the x-10 switch with the understanding that it would control an LED dimmable light. Is does not. It will dim the light bulb but it does not turn it OFF. It just dims when you switch it off with a low level light still visible. It does control an Incandescent Bulb even dimming it or turning it off completely. But is does not do what it claims - control LED bulbs.
Per the AD: XPDI3 Dimmer 120 VAC 500W Inductive Wall Switch - Works with Dimmable LED Bulbs!