Appearance of Rayon piping on boards

[cbuehler]

I am sure this has been discussed previously, but when did Rayon piping on boards start to appear and is there any definitive time frame for this?
It seems to have supplanted wool piping almost entirely towards the end of the war.
Thanks,

CB

[afrikasandman]

I’ve always considered it to be early war when it appeared but it seems like it was used up to the mid point. I know on visors it’s hard to find, but board wise it’s fairly common and most of the boards they are on are early to mid war quality. Other than the M44 boards which are always rayon. Matt

[pauke]

earlier

There are actually WW1 M-1915 straps that have the synthetic piping as well, thought not in great numbers just for general information.