Stock Keeping Unit: This is a unique identifier for a listing and can consist of numbers, letters, or a mixture of both. Fillz accepts SKUs up to 30 characters long. Fillz strongly recommends that you do not re-use SKUs (ie - if your item sells out, do not use the SKU for a different type of item).
Here are some SKU examples: SKU00001 00000001 Item0000000001 Mystore0000000001 Aug2009000001
Note: Please do not put spaces in your SKUs. While this is currently accepted by Fillz, not all marketplaces support this. Some marketplaces may remove the spaces, resulting in Fillz not being able to allocate items to orders received.