Navigator CompassFeatures: 4 1/2" (115 mm) Ritchie CombiDial and Built-in Inclinometer When mounting this Compass to a bulkhead that is NOT perpendicular (90Adeg angle) to the center-line of the boat and/or NOT vertical (90Adeg angle) to the waterline of the boat (boat on level keel), a fairing block MUST be used to make the compass so. Easily Installed, Fits 5.75" (146 mm) Mounting Hole Internal Gimbal Systems for Maximum Stability During Adverse Pitch and Roll Conditions Scientifically Matched Sapphire Jewel and Hardened Steel Pivot Dial Movement Fiberglass Reinforced Bowl 45 degree Lubber Lines Exclusive Built-in 12v Amber LED Lighting Built-in Compensators to Easily Adjust for Deviation 100% Repairable Exclusive 5-Year Ritchie Warranty Approx. Shipping Weight: 2 lbs 5 oz (1.05 kg)Notes:12v lighting standard - 24 & 32v lighting options are available. Specifications: Mounting Style: Bulkhead Lubber Lines: Yes Read: Both Backlight: Yes Box Dimensions: 7"H x 7"W x 8"L WT: 2.8 lbs UPC: 010342150301 Quick Guide (pdf)Owner&';s Manual (pdf)