This specification covers the performance requirements for NPN, silicon, power, 2N5660, 2N5660U3, 2N5661, 2N5661U3, 2N5662 and 2N5663 transistors. Three levels of product assurance (JAN, JANTX and JANTXV) are provided for each device type as specified in MIL-PRF-19500/454.