The Alaska Guide Creations Classic Gen L offers the classic design features of the original binocular harness chest pack Jaret developed 40+ years ago with today's modern advancements in innovation and durability. These are the mid-size line and are meant to accommodate full size binoculars up to around 50mm objective lenses. Most 10×50 and 12×50 binoculars would fit perfect in the classic harness.