Use to reinforce medium to heavy duty belts, and to sew heavyweight and multi-ply fabrics, canvas, and leather. Average thickness: 0.82 mm (27/1000 In). Nominal tensile strength: 150 Lbs. Needle sizes: 280/28 to 330/30

Related Products 

Kevlar Thread
kevlar thread
Kevlar thread is heat resistant to 800F. Use up to size 69 in home sewing machines. It is also one of the strongest commercially available threads, but it only comes in yellow.

Fire Retardant Sewing Thread
Fire retardant thread
Fire Retardant Sewing Thread - Use for sewing fire retardant gear like racing suits, welding apparel, and firefighting gear. Heat resistant to 700F.

Fire Retardant Embroidery Thread
Fire retardant thread
Fire Retardant Embroidery Thread - Looks and performs like regular embroidery thread. Use it for embroidering names and logos on fire retardant clothing and gear. Heat resistant to 700F.

PTFE Coated Fiberglass Thread
hand sewing needles
PTFE coated fiberglass thread is made from continuous fiberglass filaments that are heat resistant, chemical resistant, and strong. The PTFE Coating is heat resistant to 620F. The fiberglass filament has a 1022F operating temperature.

Nomex Thread
nomex thread

Nomex thread is heat resistant to 700F. Use up to size 69 in home sewing machines. With very few exceptions, it only comes in white.

Needles
groz-beckert needles 

Groz-Beckert Needles with cross reference to other brands, needle size charts, and our exclusive needle / machine use guide.

Nylon Thread
nylon thread

Polyester Thread
polyester thread

Nylon and Polyester Thread - Use a heavier weight nylon or polyester thread instead of a lighter weight Kevlar. For example, a Size 138 nylon or polyester thread has about the same strength as a Size 69 Kevlar thread, costs about 80% less, and comes in colors. But, it is twice as thick, not fire retardant, and has 25% elasticity.

Aurifil Cotton
aurifil cotton thread
Cotton thread has a lower heat resistance. It chars, but it does not melt.