Before revision: Upper: traditional method of carrying water; lower: more water can be transported easily using the roller The Hippo , or Hippo roller, is a device used to carry drinking water more easily and efficiently than traditional methods, particularly in the developing world and rural areas.
After revision: Upper: traditional method of carrying water; lower: more water can be transported easily using the roller device used to carry drinking water more easily and efficiently than traditional methods, particularly in the developing world and rural areas.