Types of injection molds

By SPI

The following classification of injection molds is used by the Society of the Plastic Industry.

Class	Cycles	Notes
101 Mold	1 Million+	Built for extremely high production. This is the highest priced mold and is made with only the highest quality materials. (Ed., Full mold drawings are typical, with fully interchangeable parts.)
102 Mold	< 1 Million	Medium to high production mold, good for abrasive materials and/or parts requiring close tolerances. This is a high quality, fairly high priced mold.
103 Mold	< 500,000	Medium production mold. This is a very popular mold for low to medium production needs. Most common price range.
104 Mold	< 100,000	Low production mold. Used only for limited production preferable with non-abrasive materials. Low to moderate price range.
105 Mold	< 500	Prototype only. This mold will be constructed in the least expensive manner possible to produce a very limited quantity of prototype parts.
I Unit Insert	500,000+	Top quality materials for medium to high production requirements
II Unit Insert	< 100,000	Similar to class 104 mold. Most commonly used insert. Low to medium production
III Unit Insert	< 500	Similar to Class 105 Mold. Least expensive insert for very limited quantities. Insert build with the least expensive materials.