Hi @Yannick Michel when you receive your graphite tape you will see that this tape has little flexibility nor mechanical strength in tension. Tape is a just a useful form to allow you to position the tape where it is needed. Once there it is enclosed and you make use of its lubrication properties and compressive strength. PTFE in contrast has considerable flexibility and directional tensile and compressive strength, as well as chemical and temperature resistance. It is specially formulated for thread filling and sealing under adverse conditions. Best Regards, Kerophile.