Are debit keys universal and usable at any location regardless of their processing network?

Debit keys are not universal and cannot be used at any location regardless of their processing network. Each debit key is typically tied to a specific payment network, such as Visa, Mastercard, or specific regional networks. This means that a card or system that utilizes a certain debit key may only work at merchants or locations that support that specific processing network. For example, if a debit key is part of the NYCE network, it will not be accepted at a location that only processes transactions through the STAR network. Thus, the functionality of debit keys is limited to those merchants that are compatible with the particular payment network they are associated with.