The Sonic Screwdriver is a flexible tool and defensive device first utilized by the Doctor in his second incarnation for opening up hatches, panels and controls. Later uses included cutting through wall sections and whilst a conventional screwdriver. All the way through the Third Doctor’s exile on Earth he had a larger and more elaborately detailed version, which had a decorated silver care for and black and yellow stripes. This version had much more functions including detecting security traps, remote detonation of mines, opening doors and restraints, creating ignition sparks and again taking away screws and fixings. Later still the Fourth Doctor remade yet any other equivalent style of Sonic Screwdriver but with many more features and functions including micro soldering of circuitry, cutting wires and bulkheads or even detonating Dalek explosives.