Each size and the number of pairs remaining in each size are written on a simple white card attached to the shoe.
In this case 5, 6, 8 indicates that there is a single pair in each of those sizes remaining.
This is intuitive to the customer and to the staff. It is also an inexpensive way to manage customer expectations of available stock and if this is an item that will be reordered it acts similar to a kanban card as well.
Where have you seen Lean today?
Where can you implement a simple and quick solution to bring more value to your customers?