The rash guard is an essential part of the GB Uniform. It is mandatory to wear the official Gracie Barra black rash guard underneath the kimono. For No Gi Classes, students must wear a Gracie Barra black board short (or black short) (as well as Gracie Barra Black Rash Guard). The uniform must be clean at all times. A dirty uniform is a sign of disrespect. The uniform must be worn at all times on the mats.