• DCF787 is compact (5.4-in front to back), and lightweight (2.0-lbs) to fit into tight areas.
• DCD778 is compact (7.5-in front to back) and lightweight (2.6-lbs) to fit into tight areas.
• Both the drill and impact have a DEWALT brushless motor which delivers up to 57% more run time over brushed.
• Both the drill and impact have an LED light with 20-second trigger release delay to provide increased visibility in dark or confined spaces.
• Soft sided storage bag is durable and includes exterior and interior pockets to help keep you organized while protecting your tools.
• Maximum initial battery voltage (measured without a workload) is 20 volts; nominal voltage is 18.
• 3-Year warranty on tools and batteries.

Details: 

The DCKSS276C2 20V MAX lithium ion Brushless hammer drill/driver/impact driver combo kit (1.3-Ah) with soft-sided storage features DEWALT Brushless motors for longer life and run time over brushed motors. The hammer drill has a two-speed transmission and LED lights for working in dark spaces. The impact driver is compact yet offers up to 1500-in lbs of max torque. Soft sided storage bag is durable and includes exterior and interior pockets to help keep you organized while protecting your tools.