PES is a polyester material.
The great thing about having an older machine (before computerization) is that all kinds of thread can be used. If you have an older machine, you can try this thread. If it doesn't work, maybe you can find another use for it. I use all kinds of thread on my older sewing machine .... for different effects. I've also put a lot of thread out for the birds and such that didn't work for me.