Here's a picture:
It has black braided thread on the outside and unbraided white thread on the inside. Don't know what you call this combo.
I don't know what either is made of or its breaking strength but it feels plenty strong for my needs.
It holds knots wonderfully and I have been using it for shoe laces, draw strings and lashing anything to anything.
It grips well in the linelocs in my living room testing but I haven't tried it with linelocs in the field.
I bought my rolls from Surplus Too in Seattle at 85 S Lander Seattle, WA 98134
Tel: (206) 447-0117 FAX: (206) 447-0323. They sell it a dollar per roll cheaper than the company that makes it.