Master Lock Co 40D Shielded Disk Padlock 2.75 in

Product Description

The MASTER LOCK CO 40D is a 2.75-inch wide, disk-shaped shielded padlock built for high-security applications where cutting and corrosion resistance are priorities. The stainless steel body delivers long-term corrosion resistance in outdoor and harsh-environment installs. Inside the lock body, two anti-saw levers resist cutting attacks. A double locking deadbolt with a key-retaining feature keeps the key captive while the shackle is open. Brass keys are included, and a broken key extraction hole simplifies field service. The cylinder offers up to 600 different key cuts, supporting keying flexibility across a site.

This padlock is suited for securing gates, storage units, utility enclosures, and equipment access points in residential, commercial, and light industrial settings. It is a common choice for HVAC, electrical, and plumbing service contractors who need a durable lock on outdoor disconnect boxes, meter enclosures, or storage trailers. The stainless steel construction makes it appropriate for pool equipment areas and other high-moisture environments where standard steel locks corrode prematurely.

Key Features

• Stainless steel body for corrosion resistance in outdoor and wet environments
• Two anti-saw levers inside the lock body deter cutting attacks
• Double locking deadbolt with key-retaining feature prevents key removal while open
• Broken key extraction hole for fast field serviceability
• Up to 600 different key cuts for site-level keying flexibility
• Compatible key blanks: Master Lock K1BOX or Ilco M1 TV 320-952
• Lifetime warranty

Compatibility

Uses Master Lock key blank K1BOX or Ilco blank M1 TV 320-952. Designed as an OEM-style shielded disk padlock for general-purpose security applications across trade and commercial environments.

Installation Notes

Installation requires no special tools beyond confirming the hasp or locking staple diameter is compatible with the shackle clearance before mounting. Inspect the mounting surface and hasp for corrosion or damage before installing the lock. In electrical or utility enclosure applications, follow NFPA 70E and applicable OSHA lockout/tagout procedures when this lock is used as part of an energy isolation program. Do not force the shackle closed if the hasp is misaligned, as this can damage the deadbolt mechanism.

Technical Specifications

• Body Width: 2.75 inches
• Body Shape: Disk
• Body Material: Stainless Steel
• Key Material: Brass
• Key Cuts: Up to 600 combinations
• Weight: 3.64 pounds
• Package Quantity: 4 per package
• Unit of Measure: EA
• Warranty: Lifetime

Standard Information

• Brand: MASTER LOCK CO
• Manufacturer Part Number: 40D