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CHU3K74067PB
Union 3K74E 5 Lever Sashlock 67mm Brass BS3621 (Chubb At Heart)
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Union (Chubb At Heart) B-3K74E 67mm Brass 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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£79.90
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Description
Union 3K74E 5 Lever Sashlock 67mm Brass BS3621 (Chubb At Heart)
When it comes to safeguarding your property, there is very little room for compromise. The Union 3K74E 5 Lever Sashlock 67mm Brass BS3621 represents the gold standard in physical security for external timber doors. Renowned for its heritage and robust engineering, this lock provides peace of mind for homeowners and business owners alike. It is a sophisticated piece of hardware designed to withstand intense physical pressure while maintaining smooth, reliable operation over many years of heavy use.
This particular model is widely recognised for its compliance with the rigorous BS3621 standard. By choosing this security solution, you are opting for a product that has been vetted by insurance companies and the police force. Its construction focuses on preventing unauthorised entry through advanced mechanical resistance, ensuring that your premises remain protected against common burglary techniques such as drilling, picking, and sawing.
Understanding the Mechanical Physics of Security
The core strength of this mortice lock lies in its internal mechanism. Most standard locks fail when subjected to high-torque or high-impact force, but this unit is built differently. It utilises a sophisticated five lever system that creates a complex internal barrier. The internal components are crafted from high-grade materials, including hardened steel rollers within the deadbolt, which are specifically designed to resist hacksaw attacks. When the bolt is thrown, these rollers rotate if a blade is applied, preventing the saw from finding a purchase and cutting through the metal.
Furthermore, the physical geometry of the deadbolt is engineered to provide maximum engagement with the striking plate. With an extended 20mm throw, the deadbolt reaches deep into the door frame. This creates a significant surface area of contact, which distributes force evenly across the frame rather than concentrating it on a single point. This design philosophy effectively mitigates the risk of the door being forced open by blunt impact or crowbar leverage, as the structural integrity of the bolt is supported by the surrounding steel casing.
The Operational Workflow for Everyday Users
Operating this lock is a seamless experience that prioritises both security and ease of use. When you approach your door, the workflow begins with the insertion of the precision-cut key. As you turn the key, you are activating the internal lever pack. Each of the five levers must be lifted to a precise height for the bolt to retract. This tactile engagement provides a satisfying sense of mechanical quality, ensuring that the bolt withdraws fully into the case to allow the door to open freely.
Internally, the system is designed for dual-action convenience. The latch bolt operates via a lever handle, allowing for quick ingress and egress during the day. When leaving the property, the deadbolt can be locked from either side of the door using the key. This symmetry in design means that the lock is not handed, making it a versatile choice for both left-hinged and right-hinged doors. The 8mm follower is manufactured from sintered iron, providing high wear resistance to ensure that the handle operation remains smooth and responsive, even after thousands of cycles.
Ergonomic Health and Compliance Standards
High-quality security hardware is not just about keeping intruders out, it is also about ensuring the safety of those inside. A lock that jams or requires excessive force to operate can become a liability in emergency situations. This model is engineered to operate with minimal friction, reducing the physical strain on the user. The internal springs and levers are calibrated to provide just enough resistance to prevent accidental operation, while remaining light enough for comfortable daily use by individuals of varying physical strengths.
Compliance is another cornerstone of this product. By meeting the BS3621:2007 standard, this item ensures that you are adhering to the requirements often set out by home insurance providers. Many insurance policies will only pay out in the event of a burglary if the locking mechanisms meet these specific security criteria. By installing this piece of hardware, you are effectively reducing the administrative burden of verifying your security setup with your insurer. It provides a clear, documented level of protection that is recognised by professionals across the security industry.
Standards
- Tested to BS3621:2007
- CE Marked
- Secured by Design approved - recommended by the Police
- Insurance approved
Commercial ROI and Long Term Value
Investing in premium hardware is a classic example of long-term value over short-term savings. While cheaper locks might seem economical at the point of purchase, they often require frequent replacement due to mechanical failure or material degradation. This unit is built to last, backed by a 25-year guarantee that speaks volumes about its durability. The steel case is finished with a silver powder coat to prevent corrosion, and the polished brass forend offers a timeless, professional aesthetic that stands up well to the elements.
From a commercial perspective, the reduction in maintenance cycles is where the real savings are found. In a business or multi-tenant environment, replacing a lock is not just about the cost of the unit, but also the labour costs associated with installation and the operational downtime of the door. By choosing a high-quality product, you minimise the need for locksmith callouts and replacement parts. Over the lifecycle of the door, this translates to a significantly lower total cost of ownership, protecting both your physical assets and your operational budget.
Technical Specifications
| Feature | Specification |
|---|---|
| Lock Type | 5 Lever Mortice Sashlock |
| Standard | BS3621:2007 |
| Case Size | 67mm (2.5 inches) |
| Backset | 40mm |
| Faceplate Dimensions | 153mm x 25mm |
| Case Height | 108mm |
| Centres | 57mm |
| Deadbolt Material | Brass with hardened steel rollers |
| Latch Bolt | Roller bolt (non-handed) |
| Follower | 8mm square sintered iron |
| Guarantee | 25 Years |
Need expert advice? If you are not sure if this mortice lock is right for your requirements, please contact our friendly team today. We are here to help you select the perfect security hardware for your specific timber door setup.
When you choose this lock, you are choosing a heritage of excellence. It is more than just a piece of metal; it is a sophisticated security system that guards your home or office. Whether you are upgrading an existing door or fitting out a new property, the reliability of this 5 lever system provides the peace of mind you deserve. Its combination of anti-drill, anti-pick, and anti-saw features makes it a formidable deterrent against even the most determined intruders.
The installation process is straightforward for a qualified professional, and the included escutcheons ensure a clean, finished look once the job is complete. With a variety of security features packed into a standard 67mm case, it is an ideal choice for those who value both aesthetics and performance. Remember that a lock is only as strong as the door it is fitted into, so always ensure that your timber door is of sufficient thickness and structural quality to support this level of security. If you have any questions regarding compatibility or installation, our team is ready to assist with your enquiry.
Specification
| Manufacturer | Union |
|---|---|
| Dimensions | 108 (H) x 67 (D) |
| Guarantee | 25 Year |
| Lock Type | Mortice Sashlock |
| Lock Operation | Lever |
| Lock Backset | 40mm |
| 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 | Polished Brass |
| Security Standards | BS3621:2007 |