Vintage (1964) 9ct Gold First Aid Opening Box Charm

What would you store inside this cool little First Aid box? It has a really secure top so it can hide anything from pills to mints, to whatever really! The top is enameled with "First Aid" in black and a red cross. There is a 9ct gold jump ring attached so it is ready to be worn.
 
You normally find these "first aid" boxes in a square shape, but we love the simple rounded shape with the hinged top - it's a real one of a kind piece. 
 
Condition: Fantastic vintage condition with light wear commensurate with age. The lid shuts securely and the hinge is smooth.
 
Hallmarks: 9 375 for 9ct gold, leopard head for london, date letter for the year 1964 and a makers mark "G&F"
 
Weight: 3.89g