I suspect foul play here, as most of the manufacturers say something along the lines of "when the green light goes out the device must be replaced". As others have said the green neon is indeed the same as the red neon, just with green phosphor on the inside. I have seen many of these devices, and the problem is always the same, that the "the green light has gone out". In all the devices I have seen the red neon has a series resistor of 270K -this is correct and gives a service life of some 30 years. The green neon however has a series resistor of 120K and dramatically overruns the green neon, such that it fails very early indeed (the phosphor often turning black). I find it something of a coincidence that 120K is the correct value for the 115V US market, could this be an excuse if this ever came to light..