2x Telephoto Conversion Lens for Canon ZR90 ZR85 ZR80 Optura 500 Easy to assemble, simply threads to the front of your existing lens system. Doubles your existing optical zoom range. Minimal or no vignette. This new lens, SGT-20 (2.0X telephoto) is designed to work with compact digital and analog camcorders having a 37mm filter thread. Each greatly expands the zoom feature of your camera, the telephoto lens will double your optical zoom, getting you twice as close without resorting to a digital telephoto mode.