The National Marker Company circuit breaker lockout is designed to keep circuit breakers safely in off position. The device tightly fastens onto double or triple pole circuit breakers to prevent unauthorized persons from hazardous situations. It is mostly to lockout electrical outlets. Lockouts are a common part of safety hazard prevention measures at facilities/jobsites with high power circuits. These lockouts accommodate most types of breaker toggles. Exposure to unexpected energized breakers can cause serious accidents. Many facilities use easy-to-secure Circuit Breaker Lockouts that are essentially automatically operating electrical switches.