The Two-bin system (also known as Two-bin Kanban) is a simple and effective visual inventory management system used to manage the inventory of small parts or materials. The system works with two bins per item:

• Bin 1 (First Bin): Contains the active stock used continuously.
• Bin 2 (Spare Bin): Contains a spare supply for when Bin 1 is empty.

When the first bin is empty, it is moved to a central location or a signal (such as a Kanban card) is sent to indicate the need for replenishment. The employee then begins using the contents of Bin 2.

This system eliminates the need for manual inventory tracking and minimizes waste due to wait times and overproduction. It is a crucial part of JIT (Just-in-Time) manufacturing, as it ensures that materials are replenished only when they are needed.

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