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MASTER LOCK Single Pole Breaker Lockout: Clamp-On - Clamp-On Circuit Breaker Lockouts
MASTER LOCKClamp-On Circuit Breaker Lockouts

MASTER LOCK Single Pole Breaker Lockout: Clamp-On

The MASTER LOCK Single Pole Breaker Lockout (MPN 491B) is a clamp-on circuit breaker lockout designed for 120/277V AC voltage and wide breaker toggles. It does not include a cable tie slot.

SKU 3G-OTH-556460

Brand
MASTER LOCK
Item
Single Pole Breaker Lockout: Clamp-On
Category
Clamp-On Circuit Breaker Lockouts
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Technical Specifications

MASTER LOCK
Manufacturer Part Number
491B
Type
For 120/277V AC Volt
For Voltage
120/277V AC
For Use With
Wide Breaker Toggles
Includes Cable Tie Slot Final
No
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MASTER LOCK Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The MASTER LOCK Single Pole Breaker Lockout (MPN 491B) is a clamp-on circuit breaker lockout designed for 120/277V AC voltage and wide breaker toggles. It does not include a cable tie slot.

Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.

Frequently Asked Questions

What is the MASTER LOCK 491B Single Pole Breaker Lockout used for?

The MASTER LOCK 491B is a clamp-on circuit breaker lockout used to secure wide breaker toggles on 120/277V AC systems during lockout/tagout procedures. It helps prevent accidental re-energization, supporting workplace safety in industrial and commercial electrical maintenance.

What are the specifications of the MASTER LOCK 491B breaker lockout?

The MASTER LOCK 491B is rated for 120/277V AC voltage and is designed for use with wide breaker toggles. It is a single-pole, clamp-on lockout device. The manufacturer part number is 491B, and it does not include a cable tie slot.

Where to buy the MASTER LOCK 491B breaker lockout worldwide?

3G Electric supplies the MASTER LOCK 491B breaker lockout to customers worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your site. Contact us for pricing and lead time on this safety device.

How to install the MASTER LOCK 491B clamp-on breaker lockout?

To install the MASTER LOCK 491B, clamp the device over the wide breaker toggle until it snaps into place. Then insert a padlock through the lockout hasp to secure it. Follow your facility's lockout/tagout procedures and verify zero energy before servicing equipment.

Used in

Common applications for MASTER LOCK
Locker security in industrial facilities — Master Lock built-in deadbolt lock (MPN 1710) for employee lockers
Equipment access control on job sites — Master Lock Bluetooth padlock (MPN 4400ECWWG) for tool cribs and gates
Key management for fleet vehicles — Master Lock lockbox (MPN 5440ECWWG) securing vehicle keys at depots
Padlock for outdoor storage units — Master Lock long shackle combination padlock (MPN 175LH) for hasps on sheds
Keyless entry for maintenance panels — Master Lock scrolling combination padlock (MPN 975DCOM) on electrical enclosures
High-security locking for warehouse cages — Master Lock stainless steel combination padlock (MPN 1500LF) for corrosion resistance

MASTER LOCK Products

3G Electric supplies MASTER LOCK clamp-on circuit breaker lockouts. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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