Room to move.
Nothing to guess.
Letter sizes alone do not tell you how a running piece will feel. Take three measurements, then compare them with verified garment dimensions before buying.

Before choosing a size
Chest
Measure around the fullest part with the tape level. Compare that number with the finished singlet or shell chest circumference.
Waist and hip
Measure where you wear your shorts and around the fullest part of your hip. Check both numbers against the garment, not only the size letter.
Length
Compare the length of a running piece you already like with the garment length. Think about the pocket and hem as you move.
This showcase does not have tested garment measurements or a verified fit chart. Ask for those before committing to a purchase.
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