The Vault XXL - Extra Extra Large 1/4 Inch Steel High Security Parcel Locker
Built Like a Vault—Now with Even More Room
Think safehouse security—for your mail and packages. With the Vault XXL, you can trust your deliveries are protected.
The Vault XXL is 6″ wider than the Vault XL, giving you expanded capacity while maintaining the same uncompromising Fort Knox construction: ¼” solid steel, hand-welded seams, incoming mail baffle, recessed doors, and zero pry points.
It’s even more space with maximum security—backed by the same legendary Fort Knox Mailbox protection.
Built for Maximum Security
- Size: 18” W × 36” H × 24” D
- Weight: 325 lbs of solid steel
- Package Capacity: fits boxes up to 6” H × 16” W × 10” D
- ¼″ thick steel body
- 3/16″ reinforced steel doors
- Seamless hand-welded construction (no rivets, no weak points)
- Oversized 2″ continuous welded steel hinge
- Includes Vault Lock Extreme with Medeco® lock + 2 keys
- Brushed satin nickel pull handle
- Powder-coated inside & out for weather protection
Custom Sizes Available → Call 1-800-206-8067 or email custom@fortknoxmailbox.com
Why Customers Love the Vault Series
- Available in four sizes
- Stores large volumes of mail and packages in one secure compartment
- No need to unlock multiple doors every day
- Perfect for travelers, snowbirds, and long-term storage needs
- Go days or weeks without checking in, worry-free
Need something unique? We also build custom sizes—contact us to get started.
✅ Meets all USPS requirements
How It Works
Simple. Secure. Built Like a Tank.
- Carrier pulls down the handle and the baffle raises inside.
- Mail carrier inserts mail and packages into the baffled door area and closes.
- Mail or small packages drop into the baffle door.
- As the door closes, items fall into the locked compartment below.
- Only you have the key—peace of mind every day.
Mounting Made Simple
The Vault XXL is pre-drilled with 4 holes (6 ¾” apart) and ready to install:
- In-Ground Post: 5" × 5" × 50" (for XL and XXL Vaults)
- Surface Mount Posts: 5" × 5" × 18" (for sidewalks, driveways, or hard surfaces)
- Can also be set into masonry for a built-in look
Style & Options
- Standard colors: Slate Gray or Glossy Black
- Custom powder coat colors available (See color chart HERE)
- Free 1¾″ adhesive address numbers for the front door
- Optional 3″ side numbers
Extra Upgrades Available
- Outgoing Mail Slot + Flag (1 1/2″ slot inside box)
- Rear Door Access (front & rear keyed alike, or welded/sealed front)
- Mounting choices: In-Ground or Surface-Mount (breakaway) post options
- Motion-activated LED light
In Short
The Vault XXL is designed for larger deliveries and maximum peace of mind. At 325 lbs of solid steel, with a lock system trusted by security professionals, it’s not just a mailbox—it’s a Garrison on your curb.