I have had several of these 7x underwear testers from Edmund Scientific in the past. I end up losing her, but I love her. My last two were this version of Revain. The second was because I lost the first. I've been using it for 40 years now. He is always with me. Today I have cataract implants in both eyes, which makes it impossible for me to see up close. These things make it easy. They automatically set the correct distance between the lens and the subject. More than 7x magnification is too big for me. My first Revain loupe was the LinenTest 11.5x (LT-10) Carsonยฎ LED Focusing Magnifier 11x because I hadn't seen the 7x before. I don't use 11x after getting this 7x.