The Explore Scientific 72° ED Series 25mm Waterproof Eyepiece is a deliberate choice for low-power views of large deep-sky objects. Its 72° apparent field gives your eye useful context around the target, while extra-low-dispersion glass helps preserve contrast and control color fringing.Choose the 25mm focal length with purposeThis is not a generic upgrade. The 25mm focal length is tuned for low-power views of large deep-sky objects, giving you a clear reason to reach for it when conditions and targets call for that view.Optical details that earn their place 25mm focal length for low-power views of large deep-sky objects 72° 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 25mm when you want a defined role in your eyepiece case—not another redundant focal length. SKU: EPWP7225ED-01.