For hard to reach places where your hand may not fit into to hold the screw on the tip of the driver.
6" to 12" would be great for common screw types. I pretty much stick to phillips but a set of differing screw head types would be nice to have around.Tried a Google search without results, obviously I am not asking the right questions. The responses I get are either non-magnetic or Rube Goldberg contraptions.
Thanks, John