Master Lock Magnum Heavy Duty Outdoor Padlock 4 Pack - Keyed-Alike

In this review the Master Lock Magnum M5XQLJ 4 pack is evaluated as a practical heavy duty option for outdoor security. The bottom line is that these padlocks are best for users who need robust, weather-resistant locks for storage, fences, toolboxes or job boxes and appreciate the convenience of keyed-alike operation. The review finds the laminated steel body, stainless steel and zinc outer components and the boron-carbide octagonal shackle deliver noticeable resistance to cutting and sawing while the covered keyway and dual ball bearings add protection against weather and prying.

Key Features

• Laminated steel body: Provides a strong core for the lock that resists impact and offers a reliable foundation for outdoor use.
• Stainless steel and zinc components: Surround the body to improve corrosion resistance for use in wet or coastal environments.
• Tough-Cut boron-carbide shackle: The octagonal 3/8 in shackle is 50% harder than hardened steel, reducing the chance of cutting or sawing through the shackle.
• 4-pin cylinder with dual ball bearings: Increases resistance to picking and prevents the shackle from being pried open under force.
• Covered keyway and shackle: Helps keep out dirt and moisture so the lock continues to operate outdoors.
• Keyed-alike 4 pack: Includes four locks opened by the same two keys for convenient single-key management.

Who It's For

The Master Lock Magnum M5XQLJ is ideal for homeowners, contractors, and storage renters who need a stout outdoor padlock for gates, storage units, toolboxes and chained equipment. Its laminated body and boron-carbide shackle make it a sensible choice where cutting resistance and weather protection matter.

Those who need very slim or low-profile locks for tight fittings should look elsewhere, since several users note the lock is substantial in size and may not fit through small hasps or narrow openings. Also, if a keyed-different set or more than two working keys per pack is required, verify key needs before purchase.

Pros & Cons

Pros

• Solid laminated construction and outer stainless/zinc components give real outdoor durability.
• Tough-Cut octagonal boron-carbide shackle resists cutting and sawing better than standard shackles.
• Dual ball bearing locking and a 4-pin cylinder add meaningful pick and pry resistance.
• Keyed-alike 4 pack simplifies access when multiple locks are used together.

Cons

• Bulky dimensions mean it may not fit through narrow hasps or tight openings described by some customers.
• Pack includes two keys for four locks, which is convenient for keyed-alike use but may be limiting if extra keys are desired.

Specifications

Lock body width	2 in (51 mm)
Shackle diameter	3/8 in (10 mm)
Shackle length	2-1/2 in (64 mm)
Shackle type	Octagonal boron-carbide Tough-Cut
Cylinder	4-pin
Locking mechanism	Dual ball bearing locking
Pack contents	Four padlocks with two keys, keyed-alike

Our Verdict

The Master Lock Magnum M5XQLJ 4 pack is a practical, heavy duty outdoor padlock set for anyone securing storage units, gates, chains or job boxes. It delivers strong cutting resistance, weather protection and convenient keyed-alike access, making it good value for users who need reliable physical security rather than a compact or slim lock.

Frequently Asked Questions

Are these locks weather resistant?
Yes. The laminated steel body is surrounded by stainless steel and zinc components and includes a covered keyway to reduce corrosion and keep out moisture.

Do all four locks use the same key?
Yes. The set is keyed-alike so both included keys open all four locks for single-key convenience.

Will the shackle resist cutting?
The octagonal boron-carbide shackle is significantly harder than standard hardened steel and offers increased resistance to cutting and sawing.