Product Details The Master Lock No. S2391 Miniature Circuit Breaker Lockout Device locks out most miniature ISO/DIN pin-out circuit breakers throughout the world. The patented device fits breakers with standard toggle openings 7/16in (11mm) or less and works with all Master Lock and American Lock safety padlocks and most hasps. Product Features * Miniature Circuit Breaker Lockout (Red Tab) – Standard Toggles) * Locks out most miniature ISO/DIN circuit breakers throughout the world * Fits breakers with toggle openings 7/16in (11mm) or less * Works with all Master Lock and American Lock safety padlocks and lockout hasps * Patented