18pcs 7 set of lenses, all?optical nitrogen?filled waterproof lenses, and prism?coated eye films. 2Waterproof marine telescope, designed for ocean and land observation, suitable for outdoor viewing, bird watching, hunting, etc. 3The internal rangefinder scale and directional compass with illuminated switch can indicate the distance or size of the observed object and its direction. 4The durable rubber coating is comfortable to hold and strong enough to withstand any conditions. 5Even under extreme conditions such as heavy rain and high humidity, the nitrogen inside the binoculars can eliminate fogging and mold on the inner lens surface. 6High?refractive?index BAK4 prisms have bright, clear images and sharped contrasts, which can provide you with every detail of objects. 7Wide lens designed, 23mm lens is more comfortable for viewing objects without causing eye fatigue, dizziness, and has a wide?angle and high?definition visual combination. 8With a large 50mm objective lens, which can provide the maximum brightness of the image even in low light conditions, such as at dusk and dawn.