Which lock do I have? Thumb turn, key turn or something else
Locksure comes in two versions because euro cylinder locks come in two common forms. The only thing you need to look at is the inside face of your door.
What is a euro cylinder?
A euro cylinder (sometimes called a euro profile cylinder or barrel) is the lock insert used on nearly every UPVC and composite door in the UK, and on many modern timber and aluminium doors. From the inside it looks like a round barrel sitting in a flat metal plate or handle backplate, with either a keyhole or a small knob in the middle. On the door edge there is a long metal faceplate with a single screw in line with the cylinder.
Thumb turn: a knob on the inside
If the inside of the cylinder has a small knob or lever you turn with your fingers, and the outside has a keyhole, you have a thumb turn cylinder. Choose the Thumb Turn monitor. One sensor fits on the inside of the door and detects locking and unlocking from either side.
Key turn: a keyhole on both sides
If there is a keyhole on the inside as well as the outside, you have a double euro cylinder, often called key-both-sides. Choose the Key Turn pack. It comes with two sensors, one for each side of the door, because the lock can be turned from either side and a single sensor cannot see the key on the far side.
Neither of those? It is probably not a euro cylinder
- A plain keyhole in a wooden door with no round barrel is a mortice deadlock. Locksure does not fit it.
- A box-shaped lock on the inside face of the door with a snib or knob is a rim nightlatch (the Yale type). Locksure does not fit it.
- A knob on the handle rather than on the cylinder is usually a privacy turn on the handle, not a thumb turn cylinder. Look for the barrel itself.
- A keypad, fob or card reader with no turning cylinder: not a fit.
One door, two versions, same job
Both versions do the same thing: they report whether the lock has been turned to locked or unlocked. Neither has a motor, so nothing can lock or unlock the door for you. The difference is only how many sensors a door needs.
| Inside of the door | Choose | Sensors per door |
|---|---|---|
| Thumb turn knob | Thumb Turn | 1 |
| Keyhole (key both sides) | Key Turn | 2 (one each side) |
| Mortice deadlock, nightlatch, keypad | Not a fit | n/a |
Next step
Now run the four checks in Will Locksure fit my lock?. If you are still unsure, send a photo through the Ask Locksure form and we will tell you.
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