The most distinctive feature in the design of this building is an aperture at the peak. The original design specified a circular aperture, 46m in diameter, to reduce the stresses of wind pressure, as well as serve as a subtext for the design, since "Chinese mythology represents the earth with a square and the sky with a circle". It also resembled a Chinese moon gate due to its circular form in Chinese architecture. However, this initial design began facing protests from some Chinese, including the mayor of Shanghai, who considered it too similar to the rising sun design of the Japanese flag. Pedersen then suggested that a bridge be placed at the bottom of the aperture to make it less circular. Later KPF submitted an alternative design to Mori Building and a trapezoidal hole replaced the circle at the top of the tower, which in addition to changing the controversial design, was also cheaper and easier to implement. In the eyes of some, the building resembles a giant bottle opener.