# Default Auto Lot Prefix
YouTube: [How to Set Default Auto lot prefixes in Purchase ?](https://www.youtube.com/watch?v=Qbwsy6WFZ3g)
## How to Set Default Auto lot prefixes in Purchase?
In this tutorial, we will explore a useful feature in **Logic ERP** that allows you to specify a **default auto lot prefix** in the **purchase configuration**. This feature ensures that lot numbers are automatically generated using a predefined prefix, streamlining inventory management.
### **Defining the Auto Lot Prefix**
* Navigate to the **Purchase Voucher Configuration**.
* Click on **Other Settings-1**.
* Then, click on **Other Settings** again.
* Navigate to the **Defaults-2** tab.
* Here, you will find the option labeled **Default Auto Lot Prefix**.
* Enter the desired **prefix** that should be used for generating lot numbers automatically.
* You can also define multiple prefixes by **separating them with a comma**.
* This setting works in combination with the **Auto Generate Lot Number** option.
This picture shows how you can define the LOT number prefix.
### **Enabling Auto Lot Generation**
* When the **Auto Generate Lot Number** setting is enabled, the system will automatically create lot numbers using:
* The predefined **prefix** from the configuration.
* A system-generated **numerical sequence** that follows the prefix.
This picture shows how you can "Auto-Generate the LOT Number".
### **Creating a New Purchase Voucher**
1. Now, let’s create a **new purchase voucher** to observe how this setting works.
2. As soon as you enter the item details, the **Auto Generate Lot Number** window will appear.
3. You can see that the predefined **lot prefix** has been applied automatically.
As you can see, the LOT number prefix has been generated.
#### **Conclusion**
By enabling this feature, businesses can ensure **consistent and structured lot numbering**, reducing manual effort and improving inventory tracking.
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