Shape: Bag Shape,Weight: 5 Kg,Material: Denim Cover , Washable,Sandbags are often placed over knees in Yoga practice during seated postures, so that knees are pressed firmly towards the floor. This is done so that inner thighs are rigorously stretched.Also use Sandbags to stretch arm behind back. Just hold the Sandbags by extending arms and shoulders back. This practice will effectively tone up the chest, arm and shoulder muscles.Putting a Sandbag on belly will improve breathing and awareness of abdominal muscles.