Helmsman CompassHelmsman Compass Features:3-3/4" CombiDamp Dial Easily Installed, Fits 4" (10.16cm) Mounting Hole (NOTE: Be sure you print the template Actual size) Exclusive Built-in Green NiteVu Night Illumination Built-in Compensators to Easily Adjust for Deviation Scientifically Matched Sapphire Jewel and Hardened Steel Pivot Dial Movement Powerful DirectiveForce Magnets for Fast Heading Lock-on Movable Sun Shield 45 Degree Lubber Lines High Temperature Composite Construction for Extended Operating Range Adapter Rings Available. Sold separately. 6" (15.24). Retrofits Existing Mounting Hole for Model No. HF-73 order H-ABLK. For Model No. HF-73W order H-AWHT 100% Repairable Exclusive 5-Year Ritchie Warranty Approx. 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.