Wera Rapidaptor 489 R T-Handle Screwdriver, Hexagon 1/4" Head x 45mm Shaft
Wera Series 400 T-Handle screwdriver is perfect for the job wherever very high loosening or tightening forces have to be transferred.  By using the blade as an extension of your lower arm you can transfer particularly high torque.  Torque is transferred positively, thereby eliminating any friction loss between the hand and the handle.