The palm-sized device designed by Qinetiq, the British defence firm that was once the government research laboratories, is pinned to the uniform and uses acoustic technology to calculate the exact position of the rifle fire.
Then a electronic voice passes on the “bearing and range” to the soldier allowing him to jump to safety and return fire.
The machine has already been purchased by the Americans for deployment in the New Year and the British are looking at a vehicle mounted version.
The device, which costs around £2,500, works by isolating the crack of the sniper rifle thanks to four microphones, a GPS system and a powerful microprocessor.
It takes less than a tenth of a second and provides the results in audio and visual formats. It can even send a grid reference via radio to supporting artillery and aircraft.
The system, which weighs less than 6oz, is so sensitive it can tell the difference between outgoing friendly fire and incoming enemy fire and can distinguish a sniper even in a gun battle.
It also works when the soldier is travelling at up to 50 mph on a vehicle.
The device has already been road tested in Iraq and Afghanistan to claims of great success.