All “Mod.Vienna” models feature 90% light transmission and employ an apochromatic design that eliminates color fringing along edges. With the latest optical design, it achieved a high eye point that ensures a wide field of view and ample eye relief, allowing you to view the entire field of view without strain, even while wearing glasses.　The body is made of a lightweight yet durable magnesium alloy. In addition to IP67 dust- and water-resistant protection (fully dustproof and waterproof for 30 minutes at a depth of 1 meter), the interior of the barrel is filled with nitrogen gas to prevent condensation on the optical elements.