The flat card design requires that the compass be installed close to the helm position and low down, for example when the vessel is helmed from the standing position. Typical applications would include being installed on the navigation console or sitting. C12Plus-0020: A recessed compass for sail or power boats, designed for mounting on horizontal surfaces. Vessel Type: Motor / Sailing Rose size: 85 mm Type of rose: Flat Graduation: Every 5.0 degrees Installation hole: 85 mm Ø Lighting: 12/24V Protective cap: Included Warranty: 5 years