Fireline® and S-Lone Fire is a pre-waxed, braided cord consisting of gel-spun polyethylene which is known as the strongest fiber, per diameter, ever created. It has an unbelievably high tensile strength and has been recommended in numerous how-to articles on beadworking

Use the Thread Zap to burn through the Fireline/S-Lon Fire thread to prevent fraying. Definitely don't use scissors.