The KG-194A is the tactical, ruggedized version of the KG-194. The KG-194A has round, militarized connectors which enable this equipment to be either bench mounted or 19" rack mounted. The KG-194A, used inconjunction with the Interface Adaptor Unit, is a direct replacement for the KG-27 in those systems using the TD-660 multiplexer. The KG-194A provides trunk encryption for the Army’s Mobile Subscriber Equipment program. The KG 194A is a key generator, providing cryptographic security for all classifications of digital data traffic, encrypting and decrypting data at rates from 9.6 Kbps to 13 Mbps. The KG-94/194/94A/194A are all cryptographically compatible with each other, as well as with the KG-81 and KG-95 within their espective data rates when used in the traditional key mode. The KG-194A is an upgrade of the KG-94A design which incorporates the FIREFLY remote rekey apability. The KG-194/194A is interoperable only with other KG-194/194As and the KIV-19 in the FIREFLY mode.