Thank you, JC.
Any reason why you wouldn't just buy a corded drill?
It's a long history, I never found a corded drill with 2-speed transmission, they are too fast with low torque, even in lower speed it's hard to control and usually damage the screws. Another reason is the keyless chuck plus the clutch which is hard to find in a corded drill. Some time ago I made a power supply with an internal 18V Ni-CD battery, so I can use when mains is not avaliable, or if I use plugged into AC it charges the battery when the trigger is not pressed and helps the motor when is pressed. Once I used all day with my old cordless drill and the battery still charged.
