Opticron T4 Trailfinder WP 10x25 Roof Prism Monocular Black. Long eye relief and a wide field of view combine with slide bar focusing for easy one hand operation. Specifications for Opticron T4 Trailfinder WP 10x25 Monocular: Manufacturer: Opticron Color: Black Magnification: 10 x Objective Lens Diameter: 25 mm Field of View Linear: 288 ft at 1000 yds Eye Relief: 17 mm Magnification Type: Fixed Features of Opticron T4 Trailfinder WP 10x25 Monocular: Compact roof prism design with easy-slide focusing mechanism;Nitrogen gas filled waterproof construction;High light transmission fully multi-coated optics;Long eye relief eyepiece with twist-type retractable eyecup;Close focus to 1.5m Included Accessories: T4 Trailfinder WP monoculars are supplied in a soft case with strap and rubber objective lens cover Package Contents: Opticron T4 Trailfinder WP 10x25 Monocular Opticron 30711: T4 Trailfinder WP 10x25 Roof Prism Monocular Black