2-20 lbs weighted vest is made of breathable black lycra,black T-Cloth and Iron Sand,comfortable to wear and take off. One size fit all bodyshape! ♥【Ergonomic Weight Distribution Design】: Balanced weight distribution of adjustable waist strap and adjustable weighted vest with inner front 7 pcs sandbags and inner back 7 pcs sandbags,total 14 pcs sandbags make the upper body weight even improves exercise efficiency.