These new 1 7/16" fit-ups have a cast metal case and special gasket that seals the lens and protects the movement from being damaged by rainwater. Both models also feature luminescent hands and dials for easy reading. These new fit-ups also use a new "soft gasket" mounting system that will help to insulate the movements from most of the damaging effects of vibration. Perfect for showers, motorcycles and other outdoor uses. Not rated for use with saltwater.