DCF620B: The DEWALT DCF620B features 4,400 RPM of no-load speed with the ability to fasten various board materials/thicknesses. This screw gun can drive up to 2,800-screws per day on a 4.0 Ah 20-Volt XR battery pack. DEWALT Screw guns are designed to withstand a dusty environment. DCBP520C: This starter kit includes 1-battery and charger. Our most powerful battery in its class, the 20-Volt Maximum DEWALT Powerstack 5.0 Ah Battery utilizes revolutionary pouch cell technology to deliver 50% more power, 50% more work per charge and 2x the lifespan. Compatible with all DEWALT 20-Volt Maximum tools and chargers, the DEWALT Powerstack 5.0 Ah Battery features an impact-resistant, rubber overmolded base and includes 3-LED Fuel Gauge state of charge indicator. Includes DCF620B and DCBP520C.