Organizational, direct support, and general support maintenance repair parts and special tools lists (including depot maintenance repair parts and special tools) for ohmmeters ZM-21A/U (NSN 6625-00-643-1030) and ZM-21B/U (NSN 6625-00-643-1030).

"March 1979."

Test set I-48-B and ohmmeter ZM-21A/U.

"November 1954."

Operator's, organizational, direct support, and general support maintenance manual : ohmmeter ZM-21/U, (NSN 5950-00-645-2191), ohmmeter ZM-21A/U, (NSN 6625-00-643-1030), and ohmmeter ZM-21B/U, (NSN 6625-00-581-2466).

"January 1977."