On Fri, 01 Aug 2008 19:31:19 -0400, Wes wrote:
Bruce L. Bergman wrote:

There are many grades, the US System is 'SO' for heavy duty rubber
jacket, Junior cord for light duty 'SJO'. The thermoplastic jacket
has a T in the mark - 'STO' and 'SJTO' The O is oil resistant, they
tack a W on the end for water resistant 'STOW'.

The J really means junior?

Youbetcha! Occam's Razor strikes again. And I have seen it
confirmed in several cable catalogs.

SO will take a lot more abuse than SJO.

-- Bruce --