spiral screwdriver
Screwdriver with interchangeable bits fitted into a mechanism for screwing or unscrewing by simply pushing the handle.
locking ring 
Blocks the spiral’s rotation allowing the tool to be used as an ordinary screwdriver.
spiral 
Mechanism converting pressure applied on the handle into the rotation motion of the blade.
ratchet 
Mechanical instrument for setting the direction of rotation of the spiral and the blade (screwing or unscrewing).