A round container with a strong magnet on the inside of the lid.
 

 
It is also possible to add log strips of the type "Micro log strips RITR" which is water-resistant and fits perfectly in this container.
 

 
Material: Aluminum 
 
Diameter: approx. 35 mm 
 
Height: approx. 20 mm 
 
Volume: approx. 15 ml