As part of the Ryobi 18V ONE+™ system of over 200 cordless tools for the home, garden, automotive, crafting and much more, the Ryobi 18V ONE+™ RB18242X Dual Pack contains 1 x 4ah & 1 x 2ah 18V batteries, perfect for DIYers who need longer runtimes. Ideal for DIYers and hobbyists who want to power their first Ryobi 18V ONE+™ tool or add more batteries to their system with increased runtimes. The innovative Ryobi Lithium+ battery technology gives more power, longer runtimes and better durability than previous lithium batteries. Featuring IntelliCell™ technology which monitors and balances individual cells to maximise runtimes, storage life and safety. Incorporating a 4-stage fuel gauge which displays the remaining power (100%, 75%, 50%, 25%). The tough pack design with built in impact protection ensures long term durability.