A clerestory wraps around the seventh through tenth floors, above the Hearst Magazine Building. Above the tenth floor, the tower's facade uses a triangular framing pattern known as a diagrid, which serves as the structural support system for the tower stories. The diagrid subdivides the tower's sides horizontally, into segments of four stories, and diagonally, into alternating upright and inverted triangles, which intersect at "nodes" along various points of the facade. There are no vertical columns within the tower proper. The arrangement of the diagrid creates chamfered "birds' mouths" at the tower's corners at the 14th, 22nd, 30th, and 38th floors. The surfaces of the "birds' mouths" are sloped plus or minus 75 degrees from the horizontal floor slabs.