Like metal casting, liquid resin casting usually starts with a male pattern, often produced from aluminum, which is fastened to a flask. A liquid mold material, such as epoxy, urethane or MY silicone is poured in. One pattern can make an unlimited number of molds. Liquid resin is then poured into the mold to produce a part. Unlike metal casting, liquid resin casting captures significantly more details, particularly when silicone is used as a mold material. Details such as threads, and surface finishes such as textures or high-gloss can be achieved straight from the mold, without secondary operations. The process is most economical in cases where the part design is very complex and where the quantity required is in the range that is not well-suited for either machining or other kinds of molding processes (generally from 25 to 50 on the low end to 3000 on the high end).