Not for prudes, but suits Seinfeld fans or more accurately, Kramer fans. 
If you know, you know. 

Fabrication: Solid colors are made from 100% ring-spun cotton; Sport Grey is 90% ring-spun cotton, 10% polyester; Heather colors are 35% cotton, 65% polyester; Graphite Heather is 65% cotton, 35% polyester.