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-0021 - Flush mountable compass for sail or power boats. Installation on horizontal surfaces Vessel Type: Motor / Sailing Rose size: 100 mm Rose type: Flat Rose graduation: Every 5.0 degrees Installation hole: 112 mm Ø Lighting: 12-24 V Protective cap: Included Warranty: 5 years