The plastic granules are heated, dyes added and then inserted into the mould. The mould is preheated to 200C closed and pressure applied until the setting process is complete. The mould is then opened and the plastic item is ejected.

Items that are manufactured in this way belong to a class of plastics known as thermosetting plastics. These type of plastics are hard, brittle and heat resistant.
Items manufactured in this manner include, ash trays, electrical switches, cooking pot and oven door handles.