Resin Transfer Molding or RTM as it is commonly referred as a "Closed Mold Process" in which reinforcement material is placed between two matching mold surfaces — one being male and another being female. The matching mold set is then closed and clamped and a low-viscosity thermoset resin is injected under moderate pressures (50 - 100 PSI typically) into the mold cavity through a port or series of ports within the mold. The resin is injected to fill all voids within the mold set and thus penetrates and wets out all surfaces of the reinforcing materials. The reinforcements may include a variety of fiber types, in various forms such as continuous fibers, mat, preforms, or woven type construction as well as a hybrid of more than one fiber type. Vacuum is sometimes used to enhance the resin flow and reduce void formation. The part is typically cured with heat. In some applications, the exothermic reaction of the resin may be sufficient for proper cure.