MIL-DTL-3933M covers the general requirements for radio and microwave frequency fixed attenuators, including chip, coaxial, leaded, and relay header attenuators (see 6.1). This specification provides three device level designators; a space level (T) part number is intended for space application, (S) screened and (N) non-screened part numbering are intended for all other applications (see 1.4).