A first for any KOWA eyepiece, the optical construction of the TE-11WZ II contains 2XD-lenses. Images are delivered with outstanding sharpness even at 60X / 70X magnification. Chromatic aberration is limited at the highest level. Eye relief of 17mm remains constant throughout the magnification range. The TE-11WZ delivers a 20% wider field of view than the previous model (TE-10Z) Specs: Eye Relief: 17.0mm Magnification: TSN-99: 30-70x Wide Zoom | TSN-880/770: 25-60x Wide Zoom Field of view (degree): TSN-99: 2.0 - 1.13 | TSN-880/770: 2.4 - 1.32 Field of view at 1000m: TSN-99: 35-20m | TSN-880/770: 42-23m Exit Pupil Diameter: TSN-99: 3.3-1.4mm | TSN-880/770: 3.5-1.5mm Relative Brightness: TSN-99: 10.9-2.0 | TSN-880/770: 12.3-2.3 Twilight Factor: TSN-99: 51.4-78.6 | TSN-880/770: 46.9-72.7 25-60x when paired with TSN-880 / TSN-770 series 30-70x when paired with TSN-99 series Suitable for the following Kowa spotting scopes: TSN -771*, TSN-772*, TSN-773, TSN-774, TSN-881*, TSN-882*, TSN-883, TSN-884, TSN-99A, TSN-99S, Telephoto lens** * Product no longer available ** Requires TP-88EC1 prism adapter |