This brief from Capezio's "Team Basics" collection is great for costumes, performances, or practice! Features include a moderate cut leg line and full seat coverage with a stitched elasticized waistband to prevent rolling. Hand wash in cold water, hang dry.
I got this brief in the pink color over 5 years ago to wear with pink tights under a ballet costume dress for a show. The material is very soft and the elastic waist band doesn't dig in. I ordered a child medium at the time (I was 9) and it fit me then. Now, I'm 14, 5'3", 80lbs and it still fits me. This garment will last you a long time. The only thing to be wary of is that the white and pink briefs are slightly see-through. It doesn't show any personal parts, but you can't wear really brightly patterned panties underneath. The black ones are also great, and have no see-through problems at all. This is defiantly a good purchase, and worth every penny.
My mom bought me a Capezio child's large brief in white in 1991, as it was required for my first performance in the Nutcracker. I wore it annually for a few years. (About 2 weeks of daily performances per year.) I still have it, over 10 years later, because it's still in good shape and might come in handy. It's not as crisply white as it once was, but what can you expect after a decade?