The Swarovski 25-50x W Eyepiece is designed for use with the Swarovski ATM/STM, ATS/STS and CTS series of spotting scopes. Providing wide-angle viewing throughout the whole zoom range, the Swarovski Optik 25-50x W eyepiece offers improved observation comfort and is an ideal lens for digiscoping as it is compatible with all of Swarovski's existing photo-adapters. The magnification range covers all of the most useful settings for birdwatching and the spherical lens optical-system gives edge-to-edge sharpness at all of them. The outer surface of the glass element of the eyepiece has a Swaroclean coating that provides a non-stick effect and helps keep the glass free from dirt and water marks and makes keeping it clean much easier.