verb cus·tom·ize \ˈkəs-tə-ˌmīz\
: to change (something) in order to fit the needs or requirements of a person.
a thing that can be added to something else in order to make it more useful, versatile, or attractive.
noun af·ter·mar·ket (ăf′tər-mär′kĭt)
The market for parts and accessories used in the upkeep or enhancement of a previous purchase, as of a car or computer.