Explorer Bulkhead Compass Features: 2 3/4" Easy to Read Direct Reading Dial Viewing is adjustable to 30 degrees 12V Night Illumination Built-in Compensators to Easily Adjust for Deviation Easily Installed Fits 3" (7.62 cm) Mounting Hole. Click here to view a template of the mounting hole Scientifically Matched Sapphire Jewel & Hardened Steel Pivot Dial Movement Powerful DirectiveForce Mags for Fast Heading Lock-on High Temperature Composite Construction for Extended Operating Range 100% Repairable Exclusive 5-Year Ritchie Warranty Product : RITCHIE V-537B EXPLORER BULKHEAD MT COMPASS BLUE DIAL Manufacturer : RITCHIE COMPASS Manufacturer Part No : V-537B UPC : 010342161208