Extremely high powers sometimes make it necessary to flatten the edge of the aperture. This rules out the possibility of sharp edges causing injury and guarantees that the sides of the frame can be properly closed. By far the major benefit of lenticulars, however, is the reduction of volume and weight which they permit.
ZEISS Single Vision Lenticular lenses (available in mineral 1.5 and 1.7 material) have been specially designed for high myopia. The edge thickness around the aperture is reduced to a minimum, resulting in a step between the flattened margin and the aperture.
Apart from contact lenses, lenticular lenses are frequently the only technical possibility available to correct high myopia.