The KYK-13 Electronic Transfer Device is a common fill device designed by the United States National Security Agency for the transfer and loading of cryptographic keys with their corresponding check word.
The KYK-13 is battery powered and uses the DS-102 protocol for key transfer.
Even though the KYK-13 was first introduced in 1976 and was supposed to have been made obsolete by the AN/CYZ-10 Data Transfer Device, it is still widely used because of its simplicity and reliability.
[1] A simpler device than the CYZ-10, the KIK-30 "Really Simple Key Loader" (RASKL) is now planned to replace the KYK-13, with up to $200 million budgeted to procure them in quantity.
[2][3] This United States military article is a stub.