The remarkable Nautilus Barometer with Inclinometer is the product of state-of-the-art technological advancements. Designed to function extremely well in punishing saltwater environments, this barometer features a hydrophobic filter, allowing air to pass through while resisting water. This uniquely constructed piece is waterproof at up to three feet for 30 minutes. The highly sensitive all-metal aneroid movements have an expanded scale for detection of the slightest variation in weather movements. This highly capable barometer features an anodized aluminum dial that has been laser-engraved for precision and appeal. The glass crystal center is securely nestled in its O-ring seat for defense against vibration, impact, and thermal expansion. It"s surrounded by durable moveable markers crafted from UV-stabilized polycarbonate. Part of the state-of-the-art Nautilus Collection, this precision instrument boasts a low-glare, satin black case constructed from color anodized and sealed solid aluminum, ensuring that the finish will not peel, bubble, or tarnish. All fasteners are stainless steel for rust-free performance. This barometer comes complete with instructions as well as the optional incorporated, fluid-dampened inclinometer. In order to calibrate movement, simply twist the case an eighth turn in order to remove, leaving the back plate on the bulkhead. This feature is especially useful for storage and anti-theft. About Weems & Plath Founded in 1928, Weems & Plath is a company steeped in the rich tradition of navigation. They offer a wide spectrum of precision instruments ranging from brass nautical clocks and barometers to binoculars and children"s books. The company"s dedication to providing the highest quality possible is evident in every step of the building process. From development to production, Weems & Plath strives to be meticulous and offer exceptional service. The rich history and high standards of Weems & Plath will carry on into the future. * Dimensions: 5.88H x 5.88W x 2.5D inches * Crafted from color anodized and sealed solid aluminum * Hydrophobic filter allows air in but resists water * Includes built-in, fluid-dampened inclinometer