USB cash drawers are not commonly used. The most common type of cash drawer is a receipt printer driven; the cash drawer is connected to and opened by the receipt printer.  A USB cash drawer is a good choice if a standard 3" receipt printer is not present, for example, any business printing receipts on full size 8”x11” carbon copy paper. For any business that does not use the standard 3” receipt printer, a USB cash drawer is the way to go.