enclosed re - programmable non - volatile memory cards include at least two sets of electrical contacts to which the internal memory is connected . the two sets of contacts have different patterns , preferably in accordance with two different contact standards such as a memory card standard and that of the universal serial bus . one memory card standard that can be followed is that of the secure digital card . the cards can thus be used with different hosts that are compatible with one set of contacts but not the other . a cover that is hinged to the card to normally cover one set of contacts can be rotated out of the way by hand when that set of contacts is being used .