<Li> Limiting the number of pending requests makes the process more sensitive and reveals inefficiencies . </Li> <P> Kanban cards are a key component of kanban and they signal the need to move materials within a production facility or to move materials from an outside supplier into the production facility . The kanban card is, in effect, a message that signals depletion of product, parts, or inventory . When received, the kanban triggers replenishment of that product, part, or inventory . Consumption, therefore, drives demand for more production, and the kanban card signals demand for more product--so kanban cards help create a demand - driven system . </P> <P> It is widely held by proponents of lean production and manufacturing that demand - driven systems lead to faster turnarounds in production and lower inventory levels, helping companies implementing such systems be more competitive . </P> <P> In the last few years, systems sending kanban signals electronically have become more widespread . While this trend is leading to a reduction in the use of kanban cards in aggregate, it is still common in modern lean production facilities to find use of kanban cards . In various software systems, kanban is used for signalling demand to suppliers through email notifications . When stock of a particular component is depleted by the quantity assigned on kanban card, a "kanban trigger" is created (which may be manual or automatic), a purchase order is released with predefined quantity for the supplier defined on the card, and the supplier is expected to dispatch material within a specified lead - time . </P>

Production kanban used together with transport kanban is known as