Candace,
I compared the thread we got today to a cone of Maxi-Lock serger thread. Both made by the same company, that's rare. Here's what the labels inside the cone read:
Maxi-Lock cone:
Manufacturer: American & Efrid Inc. Mt. Holly, N.C. 28120
Thread material: 100% Polyester
MAXI-LOCK
3000 YDS
Size: TEX 27
B in a circle Poppy Red
Blue thread cone:
Manufacturer: American & Efrid Inc. Mt. Holly, N.C. 28120
Thread material: POLY WRAP POLY
PERMA CORE
6000 YDS
Size: TEX 40
A in a circle Blue 16
So, what ever this blue thread is, it's heavier and of a different construction than the normal serger thread we have.
From the chart I have been able to find, it's about equivalent to size 40 thread.
Joe