The EC3700 econscious Ladies' 4.4 oz., 100% Organic Cotton Tank Top consists of 100% organic ringspun cotton jersey fabric. With sideseam construction, double-needle coverstitched seams, and cotton/spandex ribbed neck and armholes, this tank top rivals its big name competitors with the added benefit of organic cotton. Athletic Grey is 60% organic ringspun cotton and 40% polyester.