This is a very small light sensor. A photo resistor (also known as a photodector, or photocell) changes resistance depending on the amount of light it is exposed to.
This is a ROS programmable autonomous SLAM robot prebuilt kit that can be controlled via Gamepad. The MarvelMind IPS (Indoor Positioning System) provides indoor navigation. ODROID-XU4 SBC provides the most flexible platform possible.
100 pack of square cable tie mounts with adhesive backing. 3/4 inch.