In manufacturing, rapid prototyping is used to create a three-dimensional model of a part or product. In addition to providing 3-D visualization for digitally rendered items, rapid prototyping can be used to test the efficiency of a part or product design before it is manufactured in larger quantities. Testing may have more to do with the shape or size of a design, rather than its strength or durability, because the prototype may not be made of the same material as the final product. Today, prototypes are often created with additive layer manufacturing technology, also known as 3-D printing. Direct metal laser sintering (DMLS) may also be used to create aluminum, stainless steel or titanium prototypes. This process uses laser beams to melt and fuse metal powders into solid parts.