It is an internal turn used to operate a compatible lock or privacy mechanism without a key.
Thumbturns for Key-Free Operation from Inside
A thumbturn lets a compatible lock be operated from inside without searching for a key. MacBlair stocks door thumbturns for privacy, access and escape arrangements where the chosen lock supports this function.
The turn must match the lock or cylinder type, spindle profile, door thickness and external fitting. Confirm the required security and escape function before selecting by appearance.
Keep the spindle correctly engaged without binding the mechanism. Test locking, release and latch operation from both sides before the door is put into service. Check the wider door furniture range for compatible parts, and match the fixing arrangement with suitable door hinges where the installation requires them.
Thumbturns FAQ's
No. Cylinder, spindle, door thickness and lock function must all be compatible.
Only when the complete lock and hardware arrangement meets the required escape standard.
Misalignment, an incorrect spindle length or a binding lock can make operation stiff.
Many privacy sets include an external release. Check the room requirement and choose a complete compatible set.