Explorer Compass. Explorer Compass Features: 2-3/4″ Easy to Read Direct Reading Dial, Adjustable and Removable with Bracket and Thumbscrews, Internal Green Night Illumination, Built-in Compensators to Easily Adjust for Deviation, Scientifically Matched Sapphire Jewel & Hardened Steel Pivot Dial Movement, Powerful DirectiveForce Magnets for Fast Heading Lock-on, Movable Sun Shield, High Temperature Composite Construction for Extended Operating Range, 100% Repairable,