Moving the green slider (left) to the right will inform trucks to prioritize their deliveries to make the storage filled up to the green slider. This is useful when storage is connected to machines that need the products. Moving the red slider (right) to the left will request trucks to actively remove the products from storage until its cargo is below the red marker. This is useful when the storage needs to be emptied or is used as a temporary storage, for example for slag that needs to be dumped on the terrain.
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