Sky watcher mercury 705 az3 70mm 275 f500 achromatic refractor telescope the highly affordable sky watcher mercury series of refractor telescopes allow you to take your first steps into the fascinating world of astronomy they are supplied with good levels of equipment for both astronomical and terrestrial observations although similar externally to many other telescopes on the market these telescopes are supplied with superior 125 eyepieces and accessories not 096 or hybrid 125