Standard Specification for
Aluminum and Aluminum-Alloy Extruded Round Tubes for
This standard is issued under the fixed designation B 491/B 491M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
click below Astm B 491/B 491M – 00 pdf free download
click here Astm B 490 – 92 (Reapproved 2003) pdf free download