For any given substance, the heat capacity of a body is directly proportional to the amount of substance it contains (measured in terms of mass or moles or volume). Doubling the amount of substance in a body doubles its heat capacity, etc.
Conventional soft contacts can last up to a year; conventional rigid gas permeable (RGP) contact lenses can last even longer. Frequent or planned replacement contact lenses last one to several months. Disposable contacts last from one day (daily wear) to up to two weeks (extended wear).
CAUTION! 1  Be sure to use the special contact lens case and leave your contacts in the solution for at least 6 hours. 2  If you use hydrogen peroxide or Clear Care in some other contact lens case, you need to wash your contacts off very very very very thoroughly.