10x32mm Field Tube 10x Monocular Telescope by NOCSThe next evolution is here: introducing the Field Tube monocular, the one eyed complement to the 32mm Field Issue binocular. You asked for a waterproof monocular that didnt compromise viewing quality, so we made one. The Field Tube is submersible for 30 minutes in up to 3 feet of water, earning its IPX7 waterproof grade. Sealed tight with a medical grade O ring assembly and injected with nitrogen, this monocular is impervious to condensation or fog.