Boob Organic Cotton Maternity Nursing Singlet Tank Top 92% Organic Cotton, 8% Lycra Maternity and nursing tank is bra fiendly Soft knitted stretch fabric Dual layer for breastfeeding access 95% organic cotton and 5% elastane (spandex)Machine washable cold/Lay flat to dry US Sizing:(Order Pre-pregnancy Size) XS=0-2 S=4-6 M=8-10 L=12-14 XL=16-18 XXL=20