The materials used in Fused Deposition Modeling must have a melting point between 180 and 220 degrees Fahrenheit as well as be moldable by the machine. Due to these restrictions, there are only a few thermoplastics and ceramics which can be used. Materials which are most frequently used, most of which are thermoplastic, are ABS (Acylonitrile Butadiene Styrene) Plastics, Investment Casting Wax, Zirconia, Alumina, Chopped Carbon-Fiber Reinforced PolyEtherEtherKetone (PEEK), Polymethylmethacrylate (PMMA), and MABS (Methylmethracrylate Acylonitrile Butadiene Styrene) Plastics.