Bathroom door lock - Toilet Lock - Brass Indicator Bolt
Twin-Pack Mutex Bathroom Door Lock Knob, Color Indicator for Vacant or Occupied in Use Restroom, Thumbturn, Emergency Unlock, Fits Standard 2 1/8" Doors : Amazon.co.uk: DIY & Tools
Indicator Bolt (Vacant/Engaged) - Polished Nickel
Bathroom Toilet Lock, Door Lock Indicator Vacant/Engaged Chrome Latch Indicating DeadBolt Public Restroom Toilet Privacy Partition Door Lock Latch : Amazon.co.uk: DIY & Tools