VS1-g, which uses a glass mullion in lieu of an extruded aluminum blade, was selected for the renovation of two downtown Chicago lobby facades at 155 North Wacker Drive, Chicago. Unique to VS1-g+ is the ability to achieve all glass walls with un-spliced, full height glass fins, in this case spanning 50' clear, a record for Chicago and the US. The glass fin is 32” deep, quadruple laminated, 2” thick and is comprised of low iron, tempered glass with SG interlayers. Even at that depth the fins literally “disappear” visually when viewing the wall from the exterior.