Euro cylinder measuring guide showing how to measure side A and side B from the central fixing screw to determine the correct cylinder size for your door

Not sure which size cylinder you need?

Euro cylinders are measured in two halves, separated by the central fixing screw. Take both measurements from your existing cylinder before ordering, and match them to the size listed above.

A — Internal side
Measure from the centre of the fixing screw to the outer edge of the cylinder on the side that faces inside your home. Common sizes are 30mm, 35mm, 40mm, 45mm, or 50mm.

B — External side
Measure from the centre of the fixing screw to the outer edge of the cylinder on the side that faces outside your home. Common sizes are 30mm, 35mm, 40mm, or 45mm.

Cylinders are typically described as A/B — for example, a 35/45 cylinder has 35mm on the internal side and 45mm on the external side. Get both measurements right and the cylinder will fit your door perfectly.

Still unsure? Send a photo of your existing cylinder to info@homesecureshop.co.uk and we'll match it for you — or call 0151 521 8089 to speak to our team.

Full measuring guide
Product overview

Avocet ABS keyed alike thumb turn cylinders all work from the same key, so one key opens your front, back and side doors, with a thumb turn on the inside. Each cylinder is the ABS Quantum thumb turn: a TS007 3 star, British Kitemarked anti-snap cylinder that retrofits in place of your old lock.

Before you order

  • Order at least 2 locks from keyed alike listings. It's marked KA on the website image. You can mix thumb turns with keyed alike cylinders that have a key on both sides.
  • 3 keys are supplied between all the locks, however many you order. Need more? Add Avocet ABS additional keys (keyed alike) to your basket.
  • Delivery may take up to 7 working days, depending on the sizes ordered and whether extra keys need cutting. Contact us if you need delivery timescales.
  • Non-refundable: keyed alike and built-to-code locks are personalised, made-to-order goods.

Security features

  • Snap Secure Technology: after snapping, the cam locks against the internal locked side of the cylinder, so it can't be operated by hand
  • Anti-snap, anti-drill and anti-pick
  • TS007 3 star rating, with the British Kitemark™ stamp
  • Master Locksmith Association's Sold Secure Diamond standard

Sizes and measuring

  • Finishes: Chrome or Brass
  • Sizes: 30mm to 60mm on each side, in 5mm steps. The thumb turn goes on the inside.
  • Measurements are taken to the centre screw on this lock. See our euro cylinder measuring guide.

Please note: 30mm cylinders do not display a kitemark due to reduced numbers of key combinations. 30mm cylinders still snap off at the sacrificial point in front of the cam, so an intruder can't get into the lock case.

Need a set for several doors? Build your set and choose a type and size for each door. Only need one lock? See the standard Avocet ABS thumb turn.

Delivery & Returns

How much is delivery?

UK Mainland Delivery is £2.99 on all items no matter how many you order!

Northern Ireland, Scottish Highlands, Channel Islands £6.00.

We do not offer International Delivery (Ireland, France, Spain etc).

When will my order be dispatched?

Orders before 2pm (Monday to Friday) are usually dispatched same day but may take up to 24 hours.

When will I receive my item?

We ship on 2 working day courier. Fully Tracked. Tracking will be emailed on dispatch.

Special order items such as keyed alike locks will take longer to dispatch. Please refer to product description for lead times.

I haven't received my item?

Please email us your name, order number and date of purchase.

We prefer email as it allows us time to research and respond.

Returns Information

We operate a 30 day refunds and return policy.

If you change your mind you must return the product back to us within 30 days of delivery

Please include a copy of your invoice and a note stating reason for return.

Additional keys, locks keyed alike or built to code are non refundable as they are personalised made to order goods.

Any refund, which is due to a fault or other defect, will include a refund of the applicable delivery charges otherwise not.

It is the buyers responsibility to arrange the return of goods to us. We do not offer a collection service for returning items.

Items must be returned including original product packaging and accessories.

We reserve the right to refuse any returns that do not comply with this policy.

Please post returns to the following address:

Home Secure (Online)

Unit 5, Brookfield Drive

Liverpool, L9 7AJ

United Kingdom

Frequently Asked Questions

Keyed alike cylinders all work from the same key, so one key opens your front, back and side doors. Order at least 2, and 3 keys are supplied between all the locks.

It's anti-snap, anti-drill and anti-pick, with Snap Secure: if the front is snapped off, the cam locks against the inside of the cylinder so it can't be turned by hand. It's TS007 3 star rated and meets the Sold Secure Diamond standard.

Yes, if your door uses a standard euro cylinder. It replaces your old cylinder without changing the lock. Measure each side from the centre screw, and see our euro cylinder measuring guide.

For a detailed look at why ABS euro cylinders are a popular high-security choice — including real-world use, benefits, and local insights — read our full blog here: ABS Euro Locks in Liverpool – TS007 3-Star Anti-Snap Cylinders

Thumb-turn cylinders allow you to lock and unlock the door from the inside without a key. This makes them safer in emergencies and more convenient for everyday use, especially in homes with children or elderly occupants.