The Army uses The M-22 Steiner 8X30 with M-22 Reticle.It is shockproof,Fog proof,Waterproof and by the way is Porro-Prism.I have never seen a Roof prism Bino used by The Military.We used 10X50 Baush & Lombs WWII vintage in The Navy.They never fogged and were waterproof.