Lockout products are a physical method of isolating equipment to prevent it being re-energised or stop the release of any stored energy. This universal MCB lockout has been designed to fit almost any size of MCB, regardless of size or the position of the holes on the breaker. Simply turn off the breaker and place the lockout over the switch. Use the thumbscrew to tighten the internal grub screw onto the switch, locking the unit into place. The thumbscrew will then fold down on its integral hinge, allowing a padlock to be fitted preventing access to the thumbscrew.