LITIO is a sheet metal program that calculates flat (unfolded) sheet development of ducts, rectangle to ound transitions, cylinders, cones, pipe intersections, connections, bifurcations, elbows, etc. For HVAC, hoppers, cyclones, dust extraction, ducts, conveying systems, silos, piping, etc. To draw your sheet metal developments directly in AutoCAD R2000 and later (no need of DXF convertions).