If you use a tool to tighten self-tapping screws, it is optimal to take a 2-hour battery, if you need to drill a lot, 5 hours is better, but at the same time, the balance will be disturbed. Pros below: Item number dcd791-83372 Excellent screwdriver, I own it for 2 years, copes with its tasks perfectly. I had to smoke wood grouse 8 * 160, drill 300 timber with a diameter of 20mm. Every day in battle at a construction site, along with his older brother dcd790. They work at maximum loads and do not die. Got cons: The beat of the cartridge. It is an aesthetic defect, it does not affect the quality of work.