The Nylok locking element holds the Plunger body securely in place without the need for lock nuts or other devices. We recommend a 90 Degree countersink 1/32 larges than the major diameter of the mating thread to prevent damaging the element and reducing the locking torque.FeaturesSteel BodyPlease see individual sku to see if part is SS or Delrin NoseAll Plungers are Standard with Nylok ElementMetric Thread