- Extra-low dispersion (ED) glass for chromatic aberrationcompensation and brighter, clearer viewing
- Phase correction coated roof prism for high resolution
- Dielectric high-reflective multilayer prism coating on roof prism for the brightest view (straight models only)
- All lenses and prisms are multilayer-coated for thebrightest images
- Seven kinds of new eyepieces deliver optimum optical performance under various weather conditions; FEP-20-60 employs aspherical lens to minimize image distortion; FEP-25 LER has ultra long 32.3mm eye relief
