Mixing : Basic Mixing : Sends : Send Formats

Send Formats
Mono and Stereo Sends
When you click the Sends button on a track, you can choose from a list of mono or stereo output or bus paths.
Multichannel Sends (Pro Tools HD and Pro Tools with Complete Production Toolkit Only)
When you click the Sends button on a track, you can choose from a list of multichannel output or bus paths.