These mobiles are called NEGMOs because they are negative mobiles, revealing shadows and the changing relationships between the shapes. Although the forms never change size or shape, the spaces between them are constantly changing. Cross-lighting creates multiple shadows and subtractive layering within the shadow areas. Depending on their orientation to the light source, sometimes the shapes appear lighter than the background and at other times they appear darker than the shadows.

The mobiles can be assembled in any configuration to fit a specific venue or space. They are hand cut from rigid vinyl and styrene sheeting and assembled using custom fabricated steel connectors and hangers.