Advanced EXTRA STRONG Floss is made of the same polymer as some bullet proof jackets. Much stronger than Nylon. Gorilla Floss is made from super fine multi-filaments that produce a “scrubbing” action when used. Some people prefer this “scrubbing” action to PTFE. Lower coefficient of friction than Nylon, but not as low as PTFE. Easier to insert with less risk of tissue trauma and less risk of sudden breaking.