Be clear at a glance / Be clear at a glance

When you are outside of the toilet , you can know if there is space and you can avoid waiting inside or get in and out again and again.
The light is on means someone is there , The light is off means nobody is there ftoilets.
It is a Block-based design , it can be assembled according to the space of the toilet.
The Block-based design is easy to exchange and transport .