Helmsman CompassHelmsman Compass Features:3-3/4" PowerDamp Flat DialEasily Installed, Fits 4" (10.16cm) Mounting Hole. (NOTE: Be sure you print the template Actual size)Exclusive Built-in Green NiteVu Night IlluminationBuilt-in Compensators to Easily Adjust for DeviationScientifically Matched Sapphire Jewel and Hardened Steel Pivot Dial MovementPowerful DirectiveForce Magnets for Fast Heading Lock-onMovable Sun Shield45 Degree Lubber LinesHigh Temperature Composite Construction for Extended Operating RangeAdapter Rings Available. Sold separately. 6" (15.24). Retrofits Existing Mounting Hole for Model No. HF-72 order H-ABLK. For Model No. HF-72W order H-AWHT100% RepairableExclusive 5-Year Ritchie WarrantyApprox. Shipping Weight: 2lbs (907g)Notes: Comes standard with 12V lighting. 24 & 32V lighting options are available. Some custom built OEM models may have different lighting.For all Helmsman built before 1992 please see the service manual page 5-14 or contact Ritchie for replacement lighting.