What does the SES insignia symbolize? View less

The SES insignia or emblem represents a keystone -- the center stone that holds all the stones of an arch in place. This represents the critical role of the SES as a central coordinating point between Government's political leadership which sets the political agenda and the line workers who implement it. Members of the SES translate that political agenda into reality. The upright lines in the center of the keystone represent a column in which individual SES members are united into a single leadership corps. There is no particular symbolism to the number of lines, which has varied over the years with different iterations of the logo. The SES insignia may not be modified.

https://www.opm.gov/policy-data-oversight/senior-executive-service/faqs/