The standard 1″ commercial Insulating Glass (IG) unit consists of two lites of 1/4″ glass and a nominal 1/2″ air space. Custom IG unit designs can be fabricated with glass thicknesses ranging from 1/8″ to 3/4″ and with airspace thicknesses ranging from 3/16″ to 7/8″ having standard spacer colors of clear, bronze and black anodized, and mill finish aluminum.