100 Percent Brand New and High Quality: Multi-Coated 2 inch 80 degree F15 mm UWA telescope eyepiece; the Ultra-Wide 80 Degree Eyepieces are equipped with plastic case; which can better protect eyepieces and against dust than the cap
6-Elements in 4 Groups Design: Fully multi-coated and soft eyecup; the inside of the adapter is fully threaded to minimize reflections
Threaded for Filters and Barlow Lens: 2 inch standard female thread to fit a filter etc at the rear end; very well built
New Upgrade: Astromania Upgrade Edition OIII Filter is used for capturing the gas tails and gas flows of comets; with the two brightest C2 emission lines at wavelengths of 511 and 514 nm; the full width at half maximum wavelength is less than 15 nm
Fused Silica Matrix: The OIII filter is made of silica matrix and has an aluminum metal casing. It features dichroic interference and anti-reflective coating; it is suitable for areas with light pollution and dark sky areas to enhance contrast