Natural flax shaft packing with wax and animal fat as the lubricating material has been the packing standard for years. This packing is free of PTFE and the chief reasons for it's popularity is that it is inexpensive and readily available in most parts of the mariner's world. History shows that despite the fact this product was the standard packing replacement, it has been replaced by newer and better packings.
The drawbacks to standard flax packing are that it is not a strong fiber and the conventional lubricant (wax/animal fat) dissipates very fast, leaving only the flax fiber. In addition the natural flax has a tendency to mildew and rot, causing the flax fibers to breakdown. Many new and effective shaft packings have replaced conventional flax, yet many boat owners continue to use it as a packing replacement.