Select the General tab of the Inventory Item Defaults window to UPC/SKUmake basic choices about how inventory items will be handled in Sage 50. These choices include whether you want to allow inventory items to share UPC/SKU numbers and whether you want to buy and sell in multi-packs.
UPC/SKU: This check box lets you decide whether you want inventory items to be able to share UPC/SKU values. Check it to allow duplicate UPC/SKU numbers. (Sage 50 Quantum Accounting)
Part Number: This check box lets you decide whether you want to allow duplicate values for the Part Number field when an items share the same Preferred Vendor.
Multi-Packs:This check box lets you decide whether you want to be able to buy and sell inventory items in multi-packs and different units/measures. (Sage 50 Quantum Accounting)
Item Class: You can save time entering inventory items later by setting a default Item Class. If you are a mostly retail company, you might set this to Stock Item; if you are a service company, you might set this to Service.
You can always change the item class if needed when setting up individual inventory items.