Ideal for closely examining small jewelry components Comes in a protective leather case 18 millimeter lens 10X triplet; Goldtone Color-corrected with a focal length of one inch If you want the very best in professional optics, use our 10X triplet loupes. They are color-corrected with a focal length of one inch and have three-piece bonded lenses for distortion-free viewing. Each comes in its own leather case. 10X Triplet, Goldtone, 18 Millimeters.