Free delivery on orders over £100

How to Choose the Right Cylinder

How to Choose the Right Cylinder

Choosing the right cylinder for your lock can be a daunting task, given the variety of options available.  This guide aims to simplify the process by providing detailed insights into selecting the most suitable cylinder for your needs.

Cylinder Types

Double Cylinders

Double cylinders allow key access from both sides of the door.  They are perfect for external doors where access is needed from both inside and outside.

Key & Turn Cylinders

Key & turn cylinders feature key access on one side and a thumb turn on the other.  This design is convenient for quick exit in case of an emergency.

Half Cylinders

Half cylinders are operated by a key from one side only. They are ideal for internal doors or where access is only required from one side.

Other Cylinders

Other types of cylinders include specialized versions for specific applications, such as rim cylinders for surface-mounted locks and high-security cylinders with additional features


Cylinder Profiles

Euro Cylinders

Euro cylinders are versatile and commonly used in residential properties. They come in various types such as single, double, and key & turn.

Oval Cylinders

Oval cylinders function similarly to euro cylinders but have an oval shape.  They are typically used in commercial settings due to their robust construction and high-security features.


Security Features

Snap Resistant

Snap-resistant cylinders prevent the cylinder from being broken through force, a common method of attack.

Pick Resistant

Pick-resistant cylinders are designed to resist picking attempts, providing enhanced security.

Drill Resistant

Drill-resistant cylinders are reinforced to withstand drilling attempts, ensuring durability and protection.

Bump Resistant

Bump-resistant cylinders protect against bump key attacks, which are a common method of forced entry.


Understanding BSI Star Ratings

The British Standards Institution (BSI) provides star ratings to indicate the security level of lock cylinders, these ratings help consumers make informed decisions based on the security performance of the product.

One-Star Rating

Basic level of security, offering protection against some methods of attack.

Three-Star Rating

Highest level of security, including features like anti-snap, anti-pick, anti-drill, and anti-bump.

How To Measure Your Cylinder

To ensure you choose the correct size cylinder, measure the existing lock. Measure from the center screw hole to each end of the cylinder.  This will give you the external and internal measurements needed to select the right size.

Cylinder Finishes

Cylinders come in various finishes to match your door hardware and aesthetic preferences. Common finishes include brass, nickel, chrome, and black. Choosing the right finish ensures that your lock complements the overall look of your door.


Keyed to Differ (KD)

Each cylinder is operated by its own unique key.

Keyed Alike (KA)

Several cylinders can be operated by the same key, providing convenience for managing multiple locks.

Master Keyed (MK)

Allows different keys to open the same lock, useful in commercial properties for managing access.

Key Duplication Restrictions

Open Section

Keys can be easily duplicated by any locksmith.


Keys can only be duplicated with proof of ownership, providing an additional layer of security.


Keys can only be duplicated by the original manufacturer or authorized locksmiths, ensuring strict control over key duplication.


Guide on Which Cylinders to Choose for Typical Scenarios

Residential Front Door

For high security, opt for a three-star euro cylinder with anti-snap, anti-pick, and anti-drill features.

Commercial Properties

Consider three-star oval cylinders for their durability and high security. Master key systems can provide flexibility and ease of access control.

Internal Doors

For basic security, standard euro cylinders or keyed alike systems with a one-star rating can be used.

Wooden Doors

Rim cylinders paired with rim night latches are a suitable choice for ease of installation and replacement. Ensure they have at least a one-star rating for security.

High Traffic Areas

Durable three-star oval cylinders with high resistance to wear and tear are recommended.



By considering these factors and understanding the different types of cylinders available, you can make an informed decision to ensure your property is secure. For further assistance or specific product recommendations, feel free to contact our experts at Aldridge Security.