Optec Inc. AP2.7 x 24tpi Extension Tube Set: Versatile and Robust for Precise Telescope Adjustments

• Industry Standard Compatibility: Designed to extend the functionality of the AP2.7 inch thread, an industry standard established by Astro-Physics.
• Convenient Design Features: Each tube features female threads on one end and male threads on the other, with knurled bases for easy attachment and detachment.
• Stackable Extensions: The extension tubes can be combined and stacked, offering versatility in adjusting the optical path.
• Optimized Spacer Combinations: The four-piece set is engineered to provide all necessary extensions for fixed focal length telescopes in 1/4" (6.35mm) increments.
• Durable Material Construction: Made from high strength 6061 aluminum alloy and finished with black anodizing for durability and a sleek appearance.
• Minimized Internal Reflections: Features anti-reflection threading and internal baffles, especially in the largest tube, to reduce internal reflections.
• Non-Reflective Internal Surfaces: All internal surfaces are coated with a non-reflecting, ultra-flat black paint, enhancing imaging quality.
• Ideal for Fixed Focal Length Telescopes: A must-have accessory set for astronomers using fixed focal length telescopes who require precise spacing adjustments.
• Professional Quality: Reflects Optec’s commitment to high-quality, professional-grade astronomy equipment and accessories.
• Comprehensive Extension Solution: The set provides a complete solution for spacing and extension needs in astronomical setups.

Specifications

AP2.7 Extension Tube Set, 4-piece set

• Includes: 1/2", 3/4", 1", and 1-1/2"
• Possible spacer combinations:
• 0.5" through 3.25" with 1/4-inch increments plus 3.75" with all spacers combined. 

• Thread Specification