Smart Door Lock U400
- The Smart Lock U400 with Apple UWB hands-free unlock, Matter support, fingerprint access, IP65 design and long battery life for secure smart homes.
 Hands-Free Unlock with Apple Home Key |
 Matter over Thread |
 Rechargeable Battery |
 IP65 Rated and BHMA Certified |
 Advanced Fingerprint Reader |
 Auto Lock Assurance |
Product Info
Description
Ultra-Secure. Effortlessly Hands-Free. Future-Ready.
The Aqara Smart Lock U400 Kit is one of the world’s first Apple UWB smart locks, using advanced Ultra-Wideband (UWB) technology to detect your approach with pinpoint accuracy. Your iPhone or Apple Watch becomes a truly hands-free Apple Home Key, unlocking the door automatically — no tapping, swiping, codes, or biometric checks required.
With native Matter over Thread support, a long-lasting rechargeable battery, IP65 weather resistance, BHMA-certified hardware, and a high-precision fingerprint reader, the U400 combines convenience, security, and durability in one sleek, future-proof smart lock.
Key Features
- Hands-Free Unlock with Ultra-Wideband (UWB): Enjoy next-level convenience and security with spatially aware UWB technology. Simply approach your door with a compatible iPhone or Apple Watch and it unlocks instantly. No interaction required. UWB delivers more precise and secure detection, keeping your entry private and seamless. As the Aliro digital key standard rolls out, this experience will expand to more devices across ecosystems*.
- Advanced Fingerprint Reader: Unlock in just 0.3 seconds with a 160 × 160 pixel sensor offering up to 98.6% accuracy and an ultra-low false acceptance rate below 0.0001%. Store up to 50 fingerprints, all secured locally with AES encryption for maximum privacy**.
- Future-Proof Access Across Ecosystems: Powered by Matter over Thread, the U400 works reliably with Apple Home, Google Home, Amazon Alexa, Samsung SmartThings, and other Matter-compatible platforms. You are not locked into one brand or device — your smart home stays flexible and future-ready.
- NFC & Apple Home Key Benefits: Tap to unlock using Apple Home Key via NFC on your iPhone or Apple Watch. Supported models work even when powered off thanks to Power Reserve. Share keys remotely or create time-limited guest access for added convenience and control***.
- Multiple Ways to Unlock — Even Without Your Phone: Access your home using the anti-peep keypad, offline one-time or scheduled guest codes, an NFC card, supported apps, Siri or Alexa, preset automations, or the backup physical key with re-key support.
- Long-Lasting Power with USB-C Backup: The 4,880 mAh rechargeable battery lasts up to 6 months per charge. Recharge easily via USB-C on the lock panel. Receive clear low-battery alerts at 20%, including voice prompts and keypad indicators. If needed, use USB-C emergency power from a power bank or compatible phone — no lockouts.
- Weatherproof & BHMA Grade 3 Certified: The IP65-rated exterior resists dust and heavy rain, while BHMA Grade 3 certification ensures trusted everyday security and long-term durability.
- Smart Locking, Quiet Mode & Powerful Automations: Auto-lock engages when the door closes using a built-in gyroscope. Enable or disable it easily via the app or Action Button. Do Not Disturb mode reduces sounds for a quieter home. Create automations to trigger lights, climate control, or cameras when you unlock, and pair with the Video Doorbell G410 to see who’s outside and unlock in one smooth flow.
- Includes Aqara Hub M100: The Hub M100 pairs with the U400 as an Aqara Matter Controller, enabling remote locking and unlocking, battery and status checks, remote password management, automation creation, and Matter pairing for wider ecosystem integration.
Note:
* To use this functionality, a Thread-enabled Apple home hub, or a Thread-enabled iPhone is required.
** The access data is stored locally and is fully encrypted using the AES algorithm.
*** To use this functionality, a Thread-enabled Apple home hub, or a Thread-enabled iPhone is required.
Specifications
| Colour | Black, Silver |
| Model | DL-D06D & DL-D16D (Black, Silver) |
| Dimensions | Inner Panel: 7.01 × 2.99 × 1.85 in. (178 × 76 × 46.9 mm), Outer Panel: 6.58 × 2.99 × 1.01 in. (167 × 76 × 25.5 mm) |
| Wireless Protocol | Bluetooth 5.2, Thread, UWB, NFC |
| Operating Temperature | Operating Temperature: -18°C ~ 55°C (-0.4°F ~ 131°F) |
| Operating Humidity | 0 ~ 93% RH, non-condensing |
| What is in the Box | Smart Lock U400 × 1, Hub M100 × 1, Rechargeable Li-ion Battery × 1, User Manual × 1, Installation Diagram × 1, Key × 2, Accessories Kit × 1, Bolt & Screw Kit × 1, Mounting Plate × 1 |
Automations and Complementary Products
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Scene: A Warm Welcome Home
Arrive home after a long day and let your home prepare itself. As soon as you unlock the door in the evening, the lights turn on and the air conditioner creates the perfect atmosphere — no switches, no effort.
| Required Automation Products: | Smart Lock U400 |
 Hub M3 |
Automation Setup
IF (Condition) – Smart Lock U400 is unlocked after 18:00 // THEN (Action): Living room lights turn on AND Air conditioner turns on
Scene: One-Tap Visitor Access
When a visitor rings your Video Doorbell G410, you receive an instant alert on your phone. View the live video feed, confirm who’s at the door, and unlock it immediately — all with a single tap, wherever you are.
| Required Automation Products: | Smart Lock U400 |
 Video Doorbell G410 |
Automation Setup
IF (Condition) – Video Doorbell G410 Select is pressed // THEN (Action): Live video feed opens on your phone AND Door unlocks with one tap
Product Support Documents
- Step by step installation instruction video:
Installation Video (00:10:31) - Product User Manual:
User Manual (PDF) - Product FAQs:
Frequently Asked Questions (PDF)