This artificial sinew is polyester and it can be split down to the desired thickness like real sinew. Strong, smooth, and easy to work with. Easily splits up to 3 strands. Great for dream catchers, beading and leather crafts. 100% Polyester 1/8" wide (3.17mm) Break point 50 Lbs. (23 kg) 20 Yard Spool (18.29m) Made in USA