Our space-time is postulated to have the following characteristics: (1) the space is an ocean filled with the “Gamma elements” having energy and mass and of a certain size; (2) both time and distance are discretized by the process of light propagation from one Gamma element to the next in some process of relativistic boost of the internal energy. These postulates provide us with a theoretical basis to explain why the speed of light, c, should remain constant in all inertial reference frames. The discrete process of light propagation leads us to a set of natural units. As a result, new physically based “Planck element units” may be defined with the new mass scale being ~7.37 x 10-51 kg (~4.14 x 10-15 eV/c2). The length scale is estimated from the wavelength of the highest energy gamma rays, in the range of 1 x 10-19 m ‒ 1 x 10-25 m, and the new time scale then being in the range of 3.34 x 10-28 s ‒ 3.34 x 10-34 s. The Planck element units are shown to relate with the fundamental constants, c (speed of light), G (gravitational constant), and h (Planck constant) with the same dimensional relationship as the conventional Planck units, but the length and time units are larger than those of the latter by 109 – 1016 orders of magnitude while the mass is smaller by whopping 10-43 orders of magnitude.