Here is a feature profile on the system in Ample Sound's free instruments. Feature Profile: The Strumming Rectangle Found in: Ample Guitar M Lite II (and other Ample Sound instruments) Iso 27017 Pdf Hot Free Download [BEST]
"Rectangle" is not a standard musical term, so it is highly likely you are referring to the found in the Strummer tab of their plugin. This is a unique interface design used to visualize and program strumming patterns. Highly Compressed Ps2 Games Under 100mb Extra Quality Free - 3.79.94.248