It has been quite a few years since we last looked at any of the ersatz webbing produced at the darkest point of World War II when regular webbing production was at its most stretched. This webbing was made of two layers of cotton duck sandwiching a rubber core and sewn together. Today we are looking at an example of a shoulder strap in this substitute material: 

The first thing to note about this strap is that whilst the vertical strap is made of ersatz material, the horizontal strap is still made of standard woven cotton webbing. The vertical strap is made of two parts of 2” and 1” widths, sewn together, with ‘X’ reinforcement stitching: 

The end of the vertical strap has the usual brass tip rivetted to it to reduce the risk of damage when assembling the set through the brass buckle, the ersatz material presumably being just as vulnerable to fraying as standard webbing: 

These straps are not common today, although examples that do turn up tend to be in very good external condition. Unfortunately, the rubber core dries out so although items look in good condition on the outside, they are very stiff and no longer useable today.