BoyntonStu,
Could you simply use the RKR24 keyfob (which sends "normal" X10 RF signals) along with a TM751 (which is a RF receiver for "normal" X10 RF signals and has a built-in appliance module)?
Or am I missing the point?
Excellent, on point advice.
The KC674 or the KR19a are battery operated and would need some simple surgery to attach my leak detector switch.
It is a perfect for an emergency and/or fun remote to control the house water.
As you drive away, turn the water OFF.
I think that I will include one in every installation.
The ac powered powerflash sender is more of a "set it and forget it" leak detector.
It has contacts that are much easier to wire than to solder into a keychain remote.
Plug them into a receptacle and place the leak detection elements all around the house; under the refrigerator, under the kitchen sink, under the HWH, under the washing machine, etc.
Any one will turn off the entire house water.