The Ryobi RB4L30 4V USB Lithium 3.0Ah Battery & Power Bank is part of the latest 4V USB Lithium cordless range. It will keep your tools powered for longer and also acts as a power bank by connecting to the USB-C port, allowing you to keep your mobile devices charged on the go. The powerful 3.0Ah USB Lithium™ Battery & Power Bank keeps your tools running for longer. Connect the battery to your phone to charge on the go with the battery's power bank function. A press and hold fuel gauge button gives a quick and easy check of power level. Charge by connecting the USB-C port to a power source or inserting into a USB Lithium ported charger. As a part of the USB Lithium™ system, RB4L30 can be used in any of the USB Lithium™ range of tools.