The 5883H combines the technology of a wireless receiver and a wireless transmitter. The 5883H contains the same internal guts as a 5881ENH wireless receiver and a 5800TM wireless transmitter.
There is a difference between having a 5883H and using a combination of a 5881ENH/5800TM though. We have found out, through exhausting phone calls, that the 5883H, although using the circuitry of the 5881ENH/5800TM combo also sends out a serial number to certain wireless devices instead of using an RF house code. If you have a 5839 keypad you will only be able to use the 5883H instead of using a paired 5881ENH/5800TM.
You can pick up up to 40 wireless devices with this unit.