The Greenworks 24V 4.0Ah USB (2-Pack) Starter Kit with 4A Dual Port Charger makes it easy to keep any Greenworks 24V or 48V (2 x 24V) product ready for action. The Greenworks 24V lithium-ion platform powers over 50 indoor and outdoor products, including lawn mowers, blowers, string trimmers, chainsaws, power tools, and more! The 24V lithium-ion battery provides 20% more power and 35% more run-time delivering fade-free power with no memory loss after charging. Built-in USB ports make charging most portable devices such as phones or tablets a breeze.