Over mold: some people also call it double color (2K) or double shoot mold. The 2-color part usually made of 2 materials, one hard plastic inside and one soft plastic injection molded outsie. This part has two ways to make it. The easy way is to make 2 independent molds, during the molding process, firstly we injection the hard part for a batch using 1st mold, secondly put the hard part into 2nd mold to injection the soft plastic. The other and efficient way to make a twin molds and injectin in the double-shoot injection machine, the part made by this way has better precision usually.
Insert Mold: usually, the insert part is metal, such as copper nuts or stamping parts or die casting parts or machining parts. For insert part, we only need to make one mold and injection molding in common injection machine. The different is we need to put the insert part into the mold before molding.
UMM has engineering capacity and manufacturing experience in both over mold and insert mold.