C-4 fire protection vessel door lock
This vessel door lock incorporates double lock bolt and indicator mechanism. The lock may be operated freely by lever handle at ordinary time. When you turn the knob up to 90 inside, the red indicator will appear on the outside and the door can’t be opened by the handle except the key.
Reversing method: open the back cover, turn over the bolt. Suitable for bathroom doors of 36mm—45mm in thickness.