<HTML><FONT FACE=arial,helvetica><FONT SIZE=2 FAMILY="SANSSERIF" FACE="Arial" LANG="0">Hello,<BR>
I know that the number 6061 is an aluminum alloy number. This has to do with everything about that particular alloy, corrosion resistance, strength, grain structure, finishing, cold working, etc. and on and on. There are reference books available on metallic alloys of all different types of materials, steel, aluminum, copper brass, etc. A decent city library should have then available or if not the engineering library of a local college can help you.<BR>
Michael C</FONT></HTML>