You can add a supply that you may order from multiple suppliers. The way it works is you add your supply using the same reference number which could be a manufacturer code. You will then add the multiple suppliers and link to that supply item or you can do bulk changes using the import process.
Import Process for Bulk Changes
If you're doing bulk changes, you can use the standard import template and follow the steps below on how to enter the details.
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A. Enter the same Part Number in column A which could be a manufacturer code.
B. Indicate the supplier names in column B.
C. Put Yes for the Default Supplier and then put No for the other suppliers where you can possibly purchase the items.
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If you're adjusting just one of a couple of items, you can do it directly in by accessing Inventory → Supplies and open the supply details.
Add the multiple suppliers in Click on the Suppliers tab and add the other suppliers from there.
In the example below, our default supplier is A & G Engineering and we added two more suppliers for the same item.
Doing it this way allows you to purchase items from different suppliers and items still get allocated to the PO and Job considering that there is one common identifier which is the manufacturer code that we enter in the Part Number field.