Metric Stainless Steel Hex Lock Nuts, also known as Half Nuts or Jam Nuts, are a type of nut used to prevent a bolted joint from coming undone. These nuts are designed to be used in conjunction with a standard hex nut. They are typically half the height of a standard hex nut, which allows them to be tightened against the regular nut. This locking action helps to secure the bolted joint and prevent it from loosening or unscrewing due to vibrations or other factors. The stainless steel construction of these nuts ensures corrosion resistance and durability in various applications.