This heavy duty full sheet fresnel magnifier measures 10-3/4 x 8-1/2 inches , and has 2x power. It also has a 1 inch diameter round magnifier with a power of 4x. This is a great magnifier for school work and is excellent for map reading. In addition, each edge of the magnifier is designed with a ruler to measure in both inches and centimeters.

* This fresnel magnifier is a flat, full sheet size measuring 10-3/4 x 8-1/2 inches

* The magnifier has 2x power overall, with a diopter of 4x power

* All four straight edges are designed with ruler markings in SAE & metric (max - 9 inch & 24 cm)

* This entire fresnel magnfier is entirely distortion free, so reading is easier

* This magnifier is excellent for full page enlargement, map reading and more