The Seago MON842 is a light weight heavy duty monocular incorporating a hand bearing compass and range finder. Waterproof to JIS7 standards they are sealed against water incursion in 1 metre of water for 30 minutes. These monocular are nitrogen filled to avoid misting and float in case dropped over-board. They come in a durable protective carry case.Arthur Beale's stock these because the compass is rather impressive and it makes a great in the pocket tool for keeping watch. So light you forget you are carrying it. Takes accurate bearing of buoys you couldn't see with a standard handbearing compass and amazing value.Colour: Black/Blue Materials: Durable plastic/Rubber Special features: Rubber grips, waterproof, floating, nitrogen charged, hand bearing compass, range finder, rubber lens caps, carry bag. Magnification: 8 x Exit Pupil Diameter: 5.3 mm Eye Relief: 19 mm Weight: 360 g Monocular only Dimensions: 145 mm x 65 mm