Kowa TE 17HD (TSE 17HD) 25x Eyepiece - High Magnification Spotting Scope Eyepiece for Bird Watching, Hunting & Wildlife Observation

High-quality 25x fixed long eye relief eyepiece.
Compatible with the following current Kowa System S spotting scopes:

TSN-601/602 | TSN-663M/664M | TSN-82SV

Compatible with the following historical spotting scopes:

TSN-603/604 | TSN-661/662/663/664 | TSN-1/2/3/4 |TS-601/602 |TS-611/612/613/614 | TSN-820/820M (requires TSN-EC1A adapter ring)

The specification below is based on TSN-660M series spotting scopes. Specification changes dependent on the spotting scope model.

Exit Pupil Diameter:    2.6mm
Eye Relief:    32.0mm
Field of view (degree):    2.1
Field of view at 1000m:    37m
Magnification:    25x LER
Relative Brightness:    6.8
Twilight Factor:    40.6