From the video above, you will see that 4257 Refiner packing has a special design flexible Inconel wire core to withstand high vibration. The packing is very flexible when bent and does not show any form of stiffness when compared to low-grade similar category packing. When rubbed with your hands, no signs of graphite particles or lubricant can be seen to come off into your hands as would normally be seen in lower grade graphite packing.