Single Piece Infusion is a closed molded vacuum resin infusion process (vacuum is created under sealed plastic bag) that combines foam composite structural stringers (I-beams of a building), engineered knitted fiberglass fabrics (stitched material not woven), and vinylester resins to make our hulls (from 22’ to 37’) strong and a perfect glass-to-resin ratio every time. The process begins by adding dry knitted fiberglass and structural stringers to the inside of a hull mold. A bag is placed and sealed over the mold. Then a vacuum of one negative atmosphere is created underneath. The vinylester resin is then infused (pushed) thru tubes into the grid structure, laminate, and hull mold in one step. No excess resin, which results in unneeded weight, stays in the boat. When the resin hardens and the bag is pulled from the mold it creates a one-piece unsinkable structure, with weight uniformly distributed, more fiberglass per square foot, making an SPI boat three times stronger than one constructed using a conventional open-molded process. While the strength-to-weight ratio is greater than open-molded, polyester boats, this process also achieves a perfectly weighted hull each and every time.