K3 Smart Knob Lock
Drop-in knob replacement with 0.5s fingerprint entry
The K3 replaces a traditional door knob directly, with no extra holes to drill and no cord to run. It combines fingerprint, password, mechanical key and Tuya app entry in a knob form factor, which makes it the practical choice for retrofitting existing interior and commercial doors without touching the door leaf.
- Replaces a mechanical lock without reopening any holes indoors
- Active semiconductor fingerprint identification recognises a print in 0.5 seconds and resists fingerprint copying
- Stores up to 40 unique fingerprints
- Configurable for left or right opening doors, with auto-lock and always-open modes
- Rechargeable 1000 mAh lithium battery with MicroUSB emergency charging from a power bank
Suitable for: Facility managers and contractors retrofitting offices, institutions and interior residential doors, plus Tuya integrators.
Problems it solves
What this model is for
- Retrofit projects where drilling new holes in existing doors is not acceptable
- Sites with many interior doors that each need their own credential set
- Batteries dying on a door nobody checks
- Codes observed at the keypad in a shared corridor
Typical applications: Commercial offices and store rooms, Government departments, army, banks and hospitals, Bedrooms, hotels and residential interior doors.
Specification
| Unlocking methods | Fingerprint, password, mechanical key, Tuya app, temporary password, dynamic password |
|---|---|
| Fingerprint | Active semiconductor, 0.5 s recognition, anti-copy, up to 40 fingerprints |
| Door thickness | 35 to 50 mm |
| Installation | Direct replacement of a traditional lock, no extra drilling, no cord |
| Handing | Configurable left or right opening |
| Battery | Rechargeable 1000 mAh lithium battery, included |
| Emergency power | MicroUSB charging from a power bank |
| Material | Zinc alloy and aluminium, black or silver finish |
| Display | LCD screen readable in any light condition |
| Modes | Auto-lock and always open |
| Platform | Tuya app, Bluetooth; Tuya Gateway optional for remote control |
Quality control
Fingerprint recognition speed and anti-copy behaviour are the defining claims on this model and are exercised per unit. Handing configuration and auto-lock modes are verified before packing.
Customization
Black and silver finishes are standard. OEM and ODM scope TBC. Confirm with our engineering team.
How it compares
The K3 is the knob-format member of the keypad range. Choose the K2 deadbolt for a higher-security bolt, the K4 for a lever handle, and the K3 when the existing hardware is a knob and the installation must be non-destructive.
Installation and use
Swap the existing knob with a screwdriver, set the opening direction, then enrol fingerprints at the lock. Add a Tuya Gateway if you need remote networking control and real-time access management.
FAQ
K3 questions
Do we need to drill new holes?
No. It replaces a traditional door lock directly, with no extra hole and no cord.
How many fingerprints can it store?
Up to 40 unique fingerprints, recognised in about 0.5 seconds.
Will it fit our doors?
It fits door thickness between 35 and 50 mm and can be configured for left or right opening.
Can we manage it remotely?
Through the Tuya Smart app. Adding a Tuya Gateway enables remote networking control and real-time access management.
What happens when the battery runs flat?
Charge the lock directly from a power bank with a MicroUSB cable, or use the mechanical key.
What is it made of?
Zinc alloy and aluminium, finished in black or silver.
Minimum order quantity and lead time?
TBC. Confirm with our sales team.
Related
Other models in Keypad Lock
K1 Electronic Keypad Door Lock
Keypad deadbolt for doors with no Wi-Fi coverage
View specification →
K4 Smart Handle Lock
5-in-1 lever handle lock that fits US standard doors
View specification →
K2 Smart Deadbolt Lock
Fingerprint deadbolt with 100-fingerprint capacity
View specification →Ready to price the K3?
Send your quantity, finish and door details. We quote from the factory.