Barr and stroud sierra 20 60x80
Spotting scope area of use bird watching nature wildlife watching golf hunting magnification 20 x lens diameter 80 mm prism system porro exit pupil diameter 4 mm min focus distance 6 m twilight factor 40 relative brightness 16 focussing system individual focus viewing monocular 45 angled coating fully multi coated special features for spectacle wearers rubber armouring prismenglas bak 4