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Master Lock 4400D Indoor Bluetooth Padlock

4400D Indoor Bluetooth Padlock
4400D Indoor Bluetooth Padlock
Item# master-lock-4400d-indoor-bluetooth-padlock
Availability: Usually ships the same business day
Please contact us for more information on this item.

Same day shipping on most orders before 5:30pm EST.

Please note: Padlocks will ship separate from other items.

Your Smartphone is the Key!

Master Lock Bluetooth® Smart Padlocks turn your smart device into a key! With an advanced, easy-to-use app, you don't have to worry about losing keys, forgetting combinations, or unauthorized key duplication. True keyless convenience provides greater control and flexibility as you share access with friends, family, colleagues and employees. Enjoy peace of mind as you monitor the lock's activity and receive tamper alerts and low battery notifications. With anti-shim technology offering maximum security, these padlocks combine ergonomic features with strength, durability and reliability, making them the perfect choice for use at home, office, job site or school.

A Smarter Padlock!

Share Access
Schedule guest access days, nights or 24/7; share temporary access via manual code.

Monitor Activity
View lock history, including registration, guest addition/deletion, unlock/open/re-lock activity, tamper and low battery alerts.

Tamper Alerts
Multiple unsuccessful keypad entry attempts trigger email and app notifications.

Low Battery Alerts
Padlock LED, email and app notifications.


Key Features:

  • Your smartphone is the key to your padlock - no more lost keys or forgotten combos!
  • With free app, enjoy speed & ease of use, share access, have greater control with temporary digital keys/codes
  • Receive tamper alerts & low battery notifications
  • Replaceable CR2450 battery can be jumped with an external battery if the battery dies in the locked position
  • Backup access using an up/down/left/right directional code on the lock keypad
  • Easily add/remove guests & schedule guest access to 24/7 or limit to days or nights
  • Locker Mode allows for maintaining a locked state while the phone is stored inside of a locker
  • Lock history log tracks important lock events
  • Hardened boron alloy shackle for superior cut resistance
  • 2" (51mm) wide metal lock body
  • Shackle diameter .281" (7mm); shackle clearance: 7/8" (22mm) high, 13/16" (20mm) wide
  • Designed for indoor applications
  • Warranty Info:  Limited One (1) Year Warranty. Visit for complete warranty details.

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Replace Your Battery - Indoor Model 4400D

Bluetooth Smart Padlocks Get Started

Bluetooth Smart Padlocks - Informational

4400D Specs


How long will the 4400 series battery last?
The 4400 series battery should last at least 2 years in Touch Unlock Mode and 4 months in Swipe Unlock Mode with regular use.
What if my phone is lost or stolen?

Reset Keys allows the lock Owner to revoke all Bluetooth access to the lock, including their own. The Owner and all guests will receive updated Bluetooth credentials on their mobile devices.

To Reset Keys, the lock Owner should:

  1. Select the lock from the Locks list.
  2. Touch MANAGE LOCK in the upper right corner. Enter your passcode, if prompted.
  3. Touch the SETTINGS icon Settings Icon in the upper right corner.
  4. Touch RESET KEYS.
  5. Follow any additional instructions in the app to save the changes to your lock. This step must be completed for each lock the lost or stolen device had access to.
What if my lock battery dies?
If the lock battery dies while the lock is closed, it can be unlocked using an external battery.

When the battery has less than 20% of estimated life remaining:

  1. The center LED on the lock keypad will light yellow.
  2. An email notification will be sent to the lock owner.
  3. A Low Battery icon will appear in the app.
  4. A Low Battery warning will appear in the lock's history.

To replace the battery on the 4400 series:

  1. The center LED on the lock keypad will light yellow to indicate low battery.
  2. Unlock and open the lock.
  3. Pull out the battery drawer at the bottom of the lock and remove the old battery*.
  4. Install a new CR2450 battery with the positive (+) side facing the back of the lock.
  5. Close the battery drawer.
    *The battery drawer will only fully extend when the lock is in the open position.
Replace Battery On 4400D Series

Master Lock 4400D Indoor Bluetooth Smart Padlock Master Lock 4400D Indoor Bluetooth Smart Padlock Master Lock 4400D Indoor Bluetooth Smart Padlock