i bought this for my truck.
http://www.amazon.com/gp/product/B000BRJF62/ref=oh_o01_s00_i00_details
its a 4 switch radio controller.
pretty simple to use. you can have up to 4 devices being controled.
it can be momentary or on / off, but if you set it to momentary and you hold the button on the controller, it keeps it on.
i have mine set so it flashes my 4 fogs lights, on / off of lights (so i can turn em on when im working outside), turn on / off compressor and then my last button is my horn which is set to momentary.
Its super simple to wire up too. there are two cables which which gives power and grounds the reciever.
the 4 channels as it says in the instruction booklet states that each color or channel has two wires, take one of each color and connect it to a power source, perferably to the battery. then the other pair of the cable goes to where you want to power, aka like the selenoid. so it goes from the battery to the device you want.
as you can see from this video,
http://youtu.be/CGYY1_Ds0M8
i got 350 ft away and it was functionable, and i could of gone farther too. But, it works best in an open area like parking lot.
Where it doesnt work as good is like when you have a multi story parking lot and you park on the 3 or 4th floor and try to honk it.
like any radio device, the controller has a antenna it extends about 3" (ha)
But either way, totaly worth the money.
