The Getters are annular-ring type device having a deflector, where the deflector has a conical segment and both axial and radial locating elements. The radial locating element is U-shaped in cross section. Usually small, circular troughs filled with metals, they oxidize the gas that remain in a vacuum tube. Once the tube envelope is evacuated and sealed, the getter is heated to a high temperature causing the material to evaporate, absorbing/reacting with any residual gases and usually leaving a silver-colored metallic deposit on the inside of the envelope of the tube.