Heavy DuPont® KEVLAR® Thread, TEX 135/3, extra strong with 40 lb breaking strength. Excellent for all your sewing where extra strength and heat resistance is needed (see thread size in third picture with penny shown for comparison).
Ideal for heavy Leather stitching, Shoe, Boot, and Luggage Making or Repair, Saddlery, Canvas sewing and especially for Fireman's Boots, tools for fire performances (fire spitting, fire eating) and toys for fire play, as KEVLAR is heat resistant up to 750° Fahrenheit (begins to decompose between 800° F and 900° F). There is no flame or fire proof synthetic fiber, so KEVLAR® Thread will decompose if you hold it into a flame (mean temperature of a candle flame: 1,500° Fahrenheit!).
TO AVOID ANY CONFUSION: My pictures show, as you can see on the second picture with the penny, a cone with 8,000 yd of thread. You get one spool with the thread you order in one continuous length.