The RMA 510 gives homeowners the performance of a gasoline-powered mower without any of the hassles. Enjoy instant starting, less noise, zero gasoline costs and zero exhaust emissions. It features a 21" deck, so you can cover more lawn faster than previous models. The RMA 510 also includes a holding slot for a second battery, so you can swap batteries and be ready to cut again in seconds. It also features an adjustable handlebar, grass catcher and larger rear wheels for rough terrain. This battery-powered lawn mower is great for small to medium suburban yards. Run time may vary based on battery type, charge level and capacity, model, operating style and conditions. Batteries and chargers can be purchased separately or as a combined kit with the skin.