Linen Testers are strong magnifiers with a measuring scale. Historically they
were (and still are) used to check the thread size and the number of woven threads per square inch. They are also used extensive in thegraphic designing, desktop publishing,film and plate, photo negatives and agriculture professions.
The purpose of using a Linen Tester is to inspectquality, check fine measurements and colorseparations in graphics, measure small details and view of postage stamps, coins, examine prints or negatives.
Single 6X lens with a 30mm square glass scale in metric and imperial measurements.