This is a 4 stereo channels expansion. Several of this modules can be added to get more stereo channels. Every channel features:
Stereo input (L works as mono in)
SEND A control (switchable PRE / POST, in PRE mode the signal is present regardless to the ON / OFF / CUE switch position and channel volume control)
SEND B control (post-fader)
PAN control (only affects the master bus)
VOLUME control (affects the master, cue and POST sends)
ON / OFF / CUE switch: ON- channel is routed to the master bus
OFF- channel is muted
CUE- channel is routed to the cue bus

15 mA +12V
15 mA -12V