This versatile tank has a slim racerback that stays put—and out of your way—when you're on the move. Measurements: 30" long Size 2 Width: 11" across under the arms Size 4 Width: 12" across under the arms Size 6 Width: 13" across under the arms Size 8 Width: 14" across under the arms Size 10 Width: 15" across under the arms Size 12 Width: 16" across under the arms