A line of hollow penta prisms has been added to Edmund Industrial Optics Inc.'s inventory of optical components. According to the company, they provide all the properties of traditional glass penta prisms without the limitations of glass substrates and with shorter optical paths. Two mirrors are oriented at 45° to redirect incoming light 90° without inverting or reversing the image. A choice of enhanced aluminum or protected gold coatings is available for visible or IR applications, respectively. Beam deviations of 30, 10 or 5 arc sec are possible for both 12.7- and 25.4-mm clear apertures. Depending on the model selected, the existing wavefront varies between 0.25 and 1 wave.