The raw materials have changed a lot overtime, starting from leather to molded polycarbonate shells. These polycarbonate shells are used now because of their strength and weight. Polycarbonates received their name because they are considered polymers. These are nicely balanced features with temperature resistance and impact resistance, and last optical properties. Polycarbonate is mainly used for electronic applications and they capitalize on safety features. These polycarbonates are great insulators and having heat resistant and flame retardant properties.
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