The AN/PYQ-10 Simple Key Loader (SKL) is a ruggedized, portable, hand-held fill device, for securely receiving, storing, and transferring data between compatible cryptographic and communications equipment. The SKL was designed and built by Ralph Osterhout and then sold to Sierra Nevada Corporation, with software developed by Science Applications International Corporation (SAIC) under the auspices of the United States Army. It is intended to supplement and eventually replace the AN/CYZ-10 Data Transfer Device (DTD). The PYQ-10 provides all the functions currently resident in the CYZ-10 and incorporates new features that provide streamlined management of COMSEC key, Electronic Protection (EP) data, and Signal Operating Instructions (SOI). Cryptographic functions are performed by an embedded