Orion 08736 10mm Sirius Plossl Telescope Eyepiece (Black) This10mm focal length 1.25 inch eyepiece is ideal for all types of telescopes: reflector, refractor, and catadioptrics such as Maksutov-Cassegrains (Mak-Cass) An excellent telescope ocular for higher-power planetary and lunar observation Offers a 52 degree apparent field of view for clear, sharp images of impressively high contrast Multi-coated for maximum light throughput Great for observing small planetary nebulas and globular star clusters