This specification covers the performance requirements for NPN, silicon, low-power transistors. Four levels of product assurance are provided for each device type as specified in MIL-PRF-19500. Two levels of product assurance are provided for the unencapsulated device types 2N3019, 2N3057, and 2N3700. Radiation hardness assurance (RHA) level designators ÛÏMÛ, ÛÏDÛ, ÛÏPÛÏ, ÛÏLÛ, ÛÏRÛ, ÛÏFÛ, ÛÏGÛ and ÛÏHÛ are appended to the device prefix to identify devices, which have passed RHA requirements.