Sale is for 250 total, Microsemi JANTX1N6638US high-reliability, metallurgically bonded ultra-fast switching/signal diodes qualified to military specifications.  Come with Certification papers. (MIL-PRF-19500/578). Designed for aerospace, military, and critical high-density applications, it comes in a hermetically sealed, surface-mount D-5D (SQ-MELF) package.