I currently have 2 RF extenders, the 6000 models. Included with each extender were 4 dual IR emitter cables allowing native support for 8 devices. Presenty I'm running IR emitters to 14 devices. I do actually have the capability to run all 14 devices off my first extender. When purchasing my 4th DVD changer however, I needed to be able to send it's IR codes via my Pronto over a different RF ID so as to not also be operating my 2nd DVD changer at the same time which uses the same IR codeset. This is where the 2nd extender comes in set to Channel 0 ID 1, versus my first extender set to Channel 0 ID 0. Looking at my PCF you'll notice that I've included the RF ID in the name of each IR code device. This is a quick and easy way for me to keep track of which RF extender each of my devices is running off of without having to access the RF tab for each device.