SS 304 Nyloc Nuts have a nylon ring inserted at the end of the nut. This is a self-locking device to stop the nut undoing under constant vibration or load variations. Because of this Nylon, Nyloc Nuts not suitable for use where the temperature is liable to exceed 120 degrees Celsius. For uses where high temperatures are incurred All Stainless Locking Nuts are available . Metric Nyloc Nuts are made to Din 985 standard. All Nyloc Nuts should be used with a lubricant such as Nickel Anti-Seize to prevent ‘Galling’.