5.0 (1 review) Beta

CompX National Pin Tumbler Mailbox Lock

Sku: C9100 / C9200
Pin Tumbler Mailbox Lock main image CompX National C9100 / C9200 Mailbox Lock - Gallery Image CompX National C7120 Heavy Duty Hook Cam - Gallery Image
Pin Tumbler Mailbox Lock main image
Select Mailbox Locks:
Pin Tumbler Mailbox Lock - Clockwise Operation Details
Pin Tumbler Mailbox Lock - Clockwise Operation. NOTE: Extra keys may only be purchased with the purchase of a new lock.

Price: $22.27

173 in Stock. More on the way! Arriving by 07/13/2026.
Bulk Pricing
2 units $20.27 ea
5 units $18.27 ea
10 units $16.27 ea

SKU: C9100

Free shipping not eligible Shipping charges will apply to this item.

Extra Keys $7.17 each

To add extra keys, C9100 must be in the cart.

SKU: C9100 / C9200
Product Description
The CompX National C9100 / C9200 Mailbox Lock is a dependable replacement for worn or damaged National-brand mailbox locks. Designed as a direct replacement, this durable cam lock is commonly used in residential and centralized mailboxes.

This lock matches the USPS L-1172C form factor, making it a suitable replacement option for mailboxes originally equipped with USPS-style locks. Ideal for restoring secure mail access, the CompX C9100/C9200 mailbox lock offers smooth operation and long-lasting performance.

Please compare your existing lock’s dimensions, cam style, and rotation to ensure proper fit.

  • APPLICATION – Replaces USPS-L-1172C locks. Exterior pedestal-mounted neighborhood boxes. Has keyway dust shutter for lock protection. Clip mounted. C9100 & C9200 are the only mailbox locks approved by USPS for 4C (CBU) mailboxes. 
  • OPERATION – C9100 operates clockwise to unlock. C9200 operates counter clockwise to unlock. Key removable in locked position only.
  • KEYING – Available keyed differently only (2,000 changes).
  • PACKAGING – Includes: a spring clip, mounting nut and (3) keys.

Looking for Keys to Your Mailbox?
1000PS - 1999PS
2000PS - 2999PS
3000PS - 3999PS
4000PS - 4999PS

Heavy duty hook cam can be ordered below - click on thumbnail at left to see a larger image.

C9100 Instruction Sheet
C9200 Instruction Sheet
You may also like these Hook Cams
Heavy Duty Hook Cam
CompX National C7120
Heavy Duty Hook Cam
Heavy Duty Hook Cam
View more details
Bulk Pricing
2 units $12.07 ea
5 units $11.07 ea
10 units $10.07 ea
19 in stock
$13.07
Free shipping not eligible Shipping charges will apply to this item.
CompX National C9100-C9200-EXTRA-KEY
Extra Cut Keys for C9100 & C9200 Mailbox Lock Packages - CompX National D4301 Key Blank
Duplicate Keys for C9100 & C9200 Mailbox Lock Packages.
669 in stock
$7.17
Free shipping eligible Ships free when your cart contains only free-shipping items and totals $35+.

RECOMMENDED PRODUCTS

Product reviews
Beta
Customer feedback
Showing 1 of 1 reviews
5.0
★★★★★
★★★★★
Great fit
The key fit perfectly and arrived quickly
SKU: C9100
Sandra
Apr 22, 2026