Specifications: Tiny HD telescopes made by seiko. Eyepiece: 12mm Objective: 21mm Magnification: 10x optical magnification Ratio :8 times. Caliber :20 mm. Object diameter :20MM Field Angle :5.5 degrees Km horizon :96 m /1000 m Exit pupil diameter :2.5MM Exit pupil distance :10.3MM Final focusing distance :5M Dimensions: length 90cm, diameter 24mm, thickness 36mm Prism system: Paul Prism system. Lenses: Optical lenses. Function: Waterproof The package includes: A: 1 x 8 x 20 monoculars 1 cleaning