Each edger requires a specific battery and spool to work properly and efficiently. Some Worx batteries can be used across multiple tools, provided the voltage requirement is the same. This is convenient if you already own or are thinking of purchasing other Worx products.You may also find aftermarket batteries made by other manufacturers that are designed to fit Worx products. While these are often cheaper, they aren’t guaranteed to be as powerful or as long-lasting as Worx batteries. They also don’t come with a warranty from Worx.Regarding string trimmer spools, there are several varieties, each of which works with a specific trimmer. While the differences are subtle — and using the incorrect spool may still render the tool functional — it may not be as effective or efficient as the proper spool.