16 - 18 volt batteries, most now come with lithium battieries which
are lighter and have more lasting power, other drills are corded
DETAIL:
Manual impact drivers consist of a heavy outer sleeve that surrounds an inner core that is splined to it. The spline is curved so that when the user strikes the outer sleeve with a hammer, its downward force works on the spline to produce turning force on the core and any socket or work bit attached to it.
