spiral screwdriver
Screwdriver with interchangeable bits fitted into a mechanism for screwing or unscrewing by simply pushing the handle.
jaw 
The parts of the chuck that grip the tool to keep it firmly in place.
blade 
Thin flat part forming the end of the bit.
chuck 
Device with jaws for attaching the bit or drill to the tool.
locking ring 
Blocks the spiral’s rotation allowing the tool to be used as an ordinary screwdriver.
handle 
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).