This is an all analog synthesizer module with four channels of envelope generation. Each envelope generator has a single input, output and decay knob. This is the same envelope generator circuit as used on BMC18. It's useful for creating percussive sounds.
For complete information on this module download this PDF file.
PCBs are for sale for $8 each.
Unfinished panels are for sale for $8 each. Please read this page on unfinished panels before ordering.
If you'd like to drill your own panel, here is the drill guide that I use to make these panels. It should be printed at 300dpi.