DM6C is available with AA alkaline or Ni-MH batteries. Bulb power: ... eye, especially the retina.Features:1. DM6C is available with AA alkaline or Ni-MH batteries. Bulb power: ... of aperture Dimension of Image Angle of viewRed-free filter F2.4 F2.3 7°4424Large spot ... lxDiopter: 0D, ±1D, ±2D, ±3D, ±4D, ±6D, ±8D, ±10D, ±15D, ±20DAperture: red-free filter, Large spot, small spot, hemispotRated voltage ...