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CHU3K74080SC
Union 3K74E 5 Lever Sashlock 80mm Satin BS3621 (Chubb At Heart)
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Union (Chubb At Heart) B-3K74E 80mm Satin 5 Lever Bs Mortice Lock 2K
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| Delivery Time Frame | Delivery Information |
| Next Working Day By 1PM | When an order is placed by 3pm for next working day on certain items |
| Standard Delivery | Usually delivered in 2 to 4 working days |
| Delivery Charges | |
| UK Mainland | Prices start at £3.95 for very small items, £6.50 for small, £9.50 for medium and £20 for large/long items |
| Scottish Highlands & Islands, Northern Ireland & Ireland | Prices from £30, please see our delivery page for more info. |
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£95.88
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£79.90
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Description
Union 3K74E 5 Lever Sashlock 80mm Satin BS3621 (Chubb At Heart)
Securing your premises requires hardware that balances robust engineering with reliable daily operation. The Union 3K74E 5 Lever Sashlock 80mm Satin BS3621 (Chubb At Heart) represents the pinnacle of mortice lock technology, offering an uncompromising level of protection for timber doors. Designed for both residential and commercial environments, this lock meets the stringent BS3621 standards, ensuring it is recognised by insurance providers and law enforcement agencies across the country.
When you choose this high security sashlock, you are investing in a legacy of precision engineering. The internal mechanism, derived from the legendary Chubb designs, provides smooth operation while maintaining a formidable barrier against forced entry attempts. Whether you are upgrading your home front door or securing a commercial office space, this model delivers peace of mind through superior build quality and advanced security features.
Advanced Security and Mechanical Physics
The mechanical integrity of this locking system relies on a sophisticated interaction between the five internal levers and the hardened steel components. When a key is inserted and turned, the levers must align perfectly to allow the bolt to retract. This precision prevents unauthorised tools from manipulating the mechanism, as any slight misalignment triggers a block in the movement of the deadbolt.
The structural materials used in this item are specifically chosen to resist common attack methods. Anti-drill, anti-pick, and anti-saw features are integrated directly into the case design, ensuring that even under extreme physical stress, the lock maintains its position. The hardened steel rollers within the deadbolt are designed to rotate if a saw blade is applied, effectively neutralising the threat of cutting attacks.
- The high tensile steel construction of the case provides a rigid foundation that resists deformation during heavy impact or physical force.
- Internal levers are manufactured from high density alloys that maintain their shape and function even after thousands of operational cycles.
- The deadbolt extends a full 20mm into the keep, creating a deep engagement that is extremely difficult to bypass through leverage or prying.
- The anti-drill protection consists of hardened components that deflect drill bits, protecting the vulnerable internal tumblers from destruction.
- Every component is coated in a durable finish to prevent the oxidation and corrosion that can seize lesser quality locking mechanisms over time.
Operational Workflow and User Interaction
Interacting with this sashlock is an intuitive experience that prioritises user comfort and efficiency. When you approach the door, the operation of the lock is seamless and responsive. The key enters the escutcheon with minimal resistance, and the turning motion feels solid and positive, providing clear tactile feedback that the deadbolt has engaged or retracted.
The process of locking the door involves a simple turn of the key, which drives the brass deadbolt into the striking plate. The deliberate resistance felt during this turn confirms that the security barriers are fully deployed. Similarly, withdrawing the latch bolt via the lever handle is designed to be fluid, requiring only light pressure to retract the mechanism, which reduces the physical strain on your hands and wrists during daily use.
- Users can easily lock or unlock the deadbolt from either side of the door using the supplied keys.
- The non-handed roller bolt allows the handle to operate smoothly regardless of whether the door is hinged on the left or the right side.
- The internal follower mechanism is engineered with sintered iron to ensure that the handle action remains consistent and free from sticking.
- The provided escutcheons serve both an aesthetic and functional purpose, protecting the keyway from debris and providing a clean finish on the door surface.
- The 57mm centres provide an ergonomic spacing that prevents the handle and keyhole from feeling cramped, ensuring comfortable access for all users.
Ergonomic Health, Safety, and Compliance
Installing hardware that meets the BS3621 standard is not just about security, it is about adhering to professional safety protocols. In a commercial environment, the failure of a lock can lead to significant operational delays and safety risks. By selecting a product that is Secured by Design approved, you are ensuring that your building meets the highest possible standards for theft prevention and occupant safety.
The ergonomic design of the handle follower and the smooth action of the deadbolt mean that users do not need to apply excessive force to operate the door. This design choice is critical in high traffic areas where repetitive strain could otherwise become an issue for employees or residents. Furthermore, the reliability of this lock means fewer instances of people getting locked out or trapped, which is a vital aspect of building management and safety compliance.
Commercial ROI and Long Term Value
Investing in premium hardware like the Union 3K74E 5 Lever Sashlock 80mm Satin BS3621 (Chubb At Heart) provides a clear financial benefit over the lifespan of your property. Cheaper alternatives often suffer from internal wear and tear, necessitating frequent replacements and maintenance call-outs. This model is built to withstand decades of use, effectively amortising the initial cost over a much longer period.
Beyond the reduced frequency of replacement, the security provided by this lock protects your assets from the significant financial loss associated with burglary. Many insurance companies offer lower premiums for properties protected by BS3621-rated hardware, allowing you to recoup your investment through annual savings. Protecting your perimeter with high-quality components is one of the most effective ways to reduce administrative overhead and operational risk.
- The 25-year guarantee serves as a testament to the manufacturer confidence in the longevity of these internal components.
- By choosing a standard-compliant lock, you avoid the potential legal and insurance complications that can arise from having insufficient security measures in place.
- The modular nature of the lock allows for simple maintenance if required, ensuring that the unit can be kept in peak condition for years to come.
- The satin chrome finish provides a timeless aesthetic that does not fade, ensuring your doors maintain a professional appearance without the need for constant cleaning or refinishing.
- The comprehensive kit includes everything needed for a standard installation, reducing the need for additional parts and simplifying the project timeline.
Technical Specifications
For professional installers and property managers, the following table details the precise measurements and technical parameters of this security solution.
| Feature | Specification |
|---|---|
| Lock Type | 5 Lever Sashlock |
| Backset | 53mm |
| Case Depth | 80mm |
| Case Height | 108mm |
| Faceplate Dimensions | 153mm x 25mm |
| Centres | 57mm |
| Finish | Satin Chrome Plated |
| Key Operation | Double-sided |
| Bolt Type | Brass deadbolt with hardened steel rollers |
| Compliance | BS3621:2007 and Secured by Design |
Standards
- Tested to BS3621:2007
- CE Marked
- Secured by Design approved - recommended by the Police
- Insurance approved
Not sure if this mortice lock is right for your requirements? If you are not sure if this mortice lock is right for your requirements please contact our friendly team today.
By selecting the Union 3K74E 5 Lever Sashlock 80mm Satin BS3621 (Chubb At Heart), you are choosing a solution that is backed by decades of locksmithing expertise. This lock is not merely a piece of metal, but a sophisticated security mechanism designed to protect what matters most. Its combination of high-grade materials, rigorous testing, and user-friendly operation makes it the definitive choice for those who refuse to compromise on safety or quality. Upgrade your door hardware today and experience the difference that genuine professional-grade security can make to your peace of mind.
Expert Advice: Always verify your door thickness before installation. This model is specifically optimised for timber doors up to 50mm thick. For doors exceeding this measurement, additional hardware or custom fitting may be required to ensure the deadbolt and latch function correctly within the frame.
Specification
| Manufacturer | Union |
|---|---|
| Dimensions | 108 (H) x 80 (D) |
| Guarantee | 25 Year |
| Lock Type | Mortice Sashlock |
| Lock Operation | Lever |
| Lock Backset | 53mm |
| Lock Centres | 57mm |
| Follower Size (mm) | 8 |
| Faceplate Width | 25mm |
| Environmental Suitability | All |
| Mechanism | Sashlock |
| Door Material Suitability | Wood |
| Max Door Thickness (mm) | 50 |
| Forend Finish | Chrome |
| Security Standards | BS3621:2007 |