Sky-Watcher NirvanaTM UWA-82° 4mm high-performance eyepieces (1.25"/31.7mm) This top quality ultra wide angle 1.25” eyepieces offer an incredible jaw-dropping viewing experience. The huge 82 degree apparent field of view, superb field-edge correction and excellent contrast combine to provide a wonderfully immersive and memorable observational adventure. Work superbly in telescopes of all focal lengths. This eyepiece is constructed with 7 lens elements in 4 separate groups. This exotic eyepiece models feature large eye-lens elements and soft twist-up rubber eyecups for comfortable viewing and fully broadband multi-coated, feature blackened lens edges, internal baffling and are parfocal. Threaded to accept standard 1.25” filters.