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For technical queries please ring 0121 236 5012
For technical queries please ring 0121 236 5012

Bold SX-43 Smart Cylinder - (inside 45mm/outside 30,35,40,45mm)

by Bold
Current price £150.00
Original price £179.00
Original price £179.00 - Original price £179.00
Original price £179.00
£150.00 - £150.00
Current price £150.00
Brand: Bold
SKU 100343


Enter and leave your home without having to worry about a key with the bold Smart Lock. The bold Smart Lock has a SKG three star rating which is the heaviest possible burglary resistance classification they give.

Suitable for

The bold Smart Lock fits all doors with an internal dimension up to 35mm. The outside dimensions can be extended to 45mm by means of the supplied extensions. The distance from the centre of the cylinder to the inside of the door must not be less than 30mm.

The bold Smart Lock is designed to replace any ordinary cylinder, you simply remove the old cylinder from your door and install the bold Smart Cylinder instead.

Battery life of 2 years

The bold Smart Cylinder is easy to install without wiring. The internal battery lasts a minimum of 2 years even with intensive use of 25 activations per day. The battery status and usage are tracked and displayed in the app. You will receive a notification well in advance when the battery is due for replacement and can optionally be delivered via Bold direct delivery.

End-to-end encryption

All communication between the lock and the bold servers is encrypted in the same way as the latest online banking software. The bold Smart Lock is not vulnerable to eavesdropping on wireless signals, hacking the smartphone or other manipulation of communications.

Backup PIN

The bold Smart Lock is completely keyless, even if you’ve forgotten your smartphone or if the locks battery runs out you can always open the door with the backup PIN code. You generate this code yourself in the bold-app and enter it by turning the outside knob.


  • Inner Size: 45mm
  • Outer size: 30, 35, 40, 45mm
  • Battery: CR123A, 1550mAh
  • Battery Life: 2 years and/or 20,000 activations
  • Operating temperature inside knob: 10°C to 40°C
  • Operating temperature outside knob: -20°C to 80°C
  • IP rating outside knob: IP54
  • IP rating inside knob: IP4X
  • Certification: SKG 3 Star rating & EN15684
  • Communication: Bluetooth 4.0 or higher
  • Activation distance: 5M
  • Access control: Instant sharing and revocation of access
  • Types access schedule: Permanent, weekly, temporary push notification
  • Encryption: AES128 End-to-End
  • Works with iOS and Android


  • 1 x bold Smart Door Lock 
  • 1 x Battery CR123A
  • 3 x Length adapters
  • 1 x Installation tool
  • 1 x Cylinder locking bolt
  • 1 x Mounting screw
  • 1 x Installation book


Please ensure that you consult our Terms & Conditions before placing an order.

We advise you to book a qualified electrician to fit the items after the goods have been received and not prior to this.

We cannot be held responsible for any charges from electricians if goods arrive later than expected.

Please kindly note that orders placed for standard delivery (this is automatic and free for orders over £85.00 or £5.95 for orders under this value) are expected to be dispatched within a 3-7 working day timeframe. 

If you need an item sooner we have a fast shipping option for £8.95 that you can choose at checkout in which we aim to deliver within a 1-3 working day timeframe. 

In some cases, stock may be kept in external warehouses. If this is the case, we will inform the customer & will order this item to our store (or in some cases direct delivery to you).

For more information on delivery please click the link here to open a new tab.