DR-2.5 Rectangular Dome Magnifier has 2 flat sides for easy handling and more focused viewing area, this medium size 4x Rectangular Dome Magnifier is the ideal reading stand magnifier.This unique design takes advantage of naturally illuminating design of a bright field magnifier with the optical superiority of a thick aspheric lens, the plano base is raised .5mm to avert surface scratching. Its rectangular shape makes it easier to hold and guide along a reading path, the horizontal field of view is as wide as our Best Selling DM-2.5 Dome Magnifier