What does TS stand for in TS4x3x.25 ASTM A500 Gr B 1

[steelchef]

Hi,
I'm only accustomed to Australian Standards so would appreciate clarification of this prefix.
I assume it means Tubular Steel, but assumptions...
Thanks
James

 

[msquared48]

I've always heard Tube, Structural.

Mike McCann
MMC Engineering

 

[kslee1000]

Tube Steel 4"x2"x1/4" (wall), old US designation.

 

[kslee1000]

Sorry, 4"x[3"]x1/4"