Check the listing for details. Upgrade service charge to have suppressor cover sewn with Kevlar thread. Condition: New. Listed at 4.50 USD. This listing is for an up-grade charge to have your suppressor cover sewn with Kevlar® thread. Kevlar®/Nomex thread is one of the strongest and most fire retardant commercially available threads. It is about 2.5 times stronger than nylon, has almost no stretch, does not melt, and decomposes at 700°F. 1. Add this to your cart along with your suppressor cover from one of our suppressor cover listing. This will help us match your up-grade and cover together.2. Ask any and all question you may have prior to purchase. This thread will be used to sew the carbon felt on to the outer material. This will be the thread that is in direct contact with your suppressor. You will not receive the spool of thread shown in the picture. This is an up-grade charge only!