433Mhz refers to radio frequency based remotes, if any spec would be stated re IrD then it would be the wavelength e.g. 880nm (nanometers) but they are pretty standard I think early remotes use Infra red light to transmit the code, post 97 models use the radio frequency to transmit the code - if you have domes near the rear-view mirror and in the roof near the tailgate then you have the IrD type.