The Explore Scientific 92° ED Series 9mm Waterproof Eyepiece is a deliberate choice for high-magnification lunar, planetary, and compact deep-sky viewing. Its 92° apparent field gives your eye useful context around the target, while extra-low-dispersion glass helps preserve contrast and control color fringing.Choose the 9mm focal length with purposeThis is not a generic upgrade. The 9mm focal length is tuned for high-magnification lunar, planetary, and compact deep-sky viewing, giving you a clear reason to reach for it when conditions and targets call for that view.Optical details that earn their place 9mm focal length for high-magnification lunar, planetary, and compact deep-sky viewing 92° apparent field of view Extra-low-dispersion glass for sharpness, contrast, and more accurate color 2-inch barrel with waterproof construction Long eye relief for measured, comfortable viewing Add the 9mm when you want a defined role in your eyepiece case—not another redundant focal length. SKU: EPWP9209ED-01.