With regard to plastic, how many grams a cup has largely depends on the type of plastic used. The common plastics used in manufacturing plastic cups are Polyethylene terephthalate and, Polyethylene Terephthalate.
The former is clear and lightweight and commonly used to make disposable plastic cups. The latter is tougher and is usually used to manufacture colored heat resistant plastic cups. Two examples of how plastic cups weigh include the Member’s Mark clear plastic cups weighing 453.5 grams and Bakers and Chefs plastic cups weighing at 340 grams.
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