3 New Eye Loupes. This is a new set of 3 eye loupes. These are great for viewing stamps, coins and gems. Each lens diameter measures approximately 7/8" (22 mm). You receive: One 3x loupe with a focal distance of 3" (76 mm). One 5x loupe with a focal distance of 2" (51 mm). One 10x loupe with a focal distance of 1" (25 mm).