3-D printing is one of the hottest investing spaces in the market today, and understanding who has a competitive edge in the technology involved is crucial for investors in these companies. In this video, Motley Fool industrials analyst Blake Bos focuses on 3D Systems (DDD 4.24%), and takes a look at the type of 3-D printing technology used in each tier of its product lineup. Then, he tells investors how 3D Systems' technology stacks up against its competition.