Exemption for small processors: integrated mills excluded under amended excise rules, administrative classification upheld as valid. The amendment narrows excise exemption eligibility by excluding units that both produce single yarn and perform downstream processing; the exemption is confined to processors performing only post spinning activities or small job work units. The administrative rationale distinguishes low capital small processors from high capital integrated mills, and the classification of 'Independent Small Processors' as the intended beneficiaries supports the exclusion of integrated units as a non arbitrary policy choice.