CNC machining is a subtractive manufacturing process, where raw material is removed with a variety of precision cutting tools to make a part or product.                       Advantages: 1 Various material: ABS(yellow, black),PC(clear, black),POM(Black,white) PP(Black,white),PMMA(clear),PBT(white),PA6+GF30(black) Bakelite (yellow) Aluminum,Stainless steel,Copper,Brass etc 2 Different surface treatment: Paint,Smoke,Polish,Silk Print,Electroplate,Sand Blast,UV-off,Powder Coat etc.         3 Good for big parts and save costs Sometimes parts are too big, then we need to take apart and glue together. In this way, a lot of time and costs will be saved.