DEWALT 20V MAX Compact Lithium-Ion 4.0Ah Battery Pack with 12V to 20V MAX Charger DCB240C - The Home Depot
DEWALT 6-Piece Cordless Brushless 20-volt Max 3-speed Oscillating Multi-Tool Kit with Soft Case (1-Battery Included) in the Oscillating Tool Kits department at Lowes.com