Lightweight Hydrocal has been specially formulated for terrain model builders. It is half the weight of Hydrocal and goes twice as far. It is the tough, quick-setting product you will prefer. Create your own castings or use it to cast rocks or create your own castings. Create a hard shell terrain, use as an adhesive to attach or fill in around castings or use it to strengthen existing terrain. Stain with Earth Colors Description 1/2 gal (1.89 L) Net wt. 2 lbs (907g)