This model is discontinued and replaced by ATA303R .
Since this transmitter with Green buttons is special using 303MHZ to defeat interference from 433MHZ surrounded. So remotes with green button is compatible with ATA 303MHZ receiver only, NOT COMPATIBLE with PTX-4BG (Grey button), PTX4BR (Red button) and PTX4PP(pink) which frequency is 433MHZ.
This replacement has one button that's ok if you operate one door only.
If you use ATA303 to operate two doors you have to order two of ATA303R .
This one has been upgraded to ATA303R.