TT-F-325A, FEDERAL SPECIFICATION: FILLER, ENGRAVING, STAMPED MARKING (16-SEP-1965)

TT-F-325A, FEDERAL SPECIFICATION: FILLER, ENGRAVING, STAMPED MARKING (16-SEP-1965)., The filler covered by this specification is a semisolidified compound of drying oil or resin and pigment which, when applied to engraved or stamped markings or graduations, hardens and becomes a permanent filler.