(2) 20V 4ah Batteries. Astro 30570 20V 7″ Brushless Variable Speed Rotary Polisher Kit. (1) 7” Brushless Variable Speed Polisher w/handle. Battery Ampere-hour (Ah): 4ah. Number of Batteries: 2x 4ah. Perfectly balanced at the hand and weighs 1lb less with battery attached than the industry’s most popular corded 7″ polisher.