High-quality, accurate instruments with excellent optics are popular with both beginning and professional navigators. Constructed from lightweight, corrosion-resistant aluminum, the Astra IIIB is electrically lighted by LED on the arc and drum. Rectangular index mirrors are standard on both models, though mirrors on the Astra are easily and conveniently interchangeable. The traditional half-silvered mirror is preferred by many experienced mariners, while the whole horizon mirror is often easier for beginners to use. A 3.5 x 40 monocular telescope is also included. 

• Frame Material: Aluminum 
• Sighting System: Traditional half-silvered or whole horizon mirror 
• Scope Magnification: 3.5 x 40 
• Filter Shields: 4 index - 3 horizon 
• Arc Range: ±20", throughout the arc 
• Drum Calibration: -5° = 130°, radius 153mm 
• Lighting: LED on the arc and drum 
• Weight: 2.6lbs 
• Case: Varnished wood carrying case 
• Included Accessories: Case, instruction book, certificate of accuracy, vial of oil, adjusting wrench 
• Warranty: 30 Days

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