The bushnell natureview 8x42s are a pair of rugged non slip rubber binoculars specifically aimed at the serious birders and naturalists the ultra close focus capabilities get you intimate with the details while the bak 4 roof prisms and fully multi coated optics ensure superior light transmission brighter and clearer images with edge to edge sharpness extended eye relief 175mm reduces eyestrain for eyeglass wearers during long observation periods its waterproof and fogproof construction