New retroreflector (Trihedral Prism) Designed to reflect any beam of light, regardless of the orientation of the prism face, back to its origin. This is a high quality custom optic Mfg. by Tyrolit Co. It has the apex flattened, polished, and an infrared pass filter bonded to it. The filter passes light longer than ~820nm. The filter can be remove with a heat gun to reveal a triangle shaped aperture with .575″ sides. Dimensions of the cube is 2.9″ Dia. x 1.42″ Depth (including IR filter).