Geometry abstract greek Stock Vector Images Alamy Math Symbols sigma icon vector from math symbols collection. Thin line sigma outline Sigma Will Increase Prices in the US on June 2 Because of Tariffs 6sigma Six Sigma Core Laboratory At Abbott Illustration artistiques Sigma Male Europosters. Show your life membership status with the Sigma Gamma Rho Life Member T Shirt. This black t shirt features SGR and 'Life Member' text for a classic, timeless style. Show your dedication to this fraternal organization in style.