TEADIT 25 BI is a bi-directionally expanded PTFE gasket-tape, produced from 100% pure PTFE (Polytetrafluoroethylene). The whole production process is subject to strictest quality control, registered under ISO 9001. This special manufacturing process results in almost equal tensile strength in both the longitudinal and cross direction. As a result of this, the material does not change its width under compression. This is in stark contrast to normal expanded PTFE tapes!