Optec DSI 3.5" Extension Tube Set, 4-Piece

Starting Price: $195.00
Price as Configured: $195.00
Brand: Optec / SKU: OP-19889

Optec-DSI 3.5-inch extension tubes feature female threads on one end with male threads on the opposite end with knurled bases to help attach and detach these tubes.  The extensions can be combined and stacked. Optec's four and five piece sets will provide all the needed extension for fixed focal length telescopes with 1/4" (6.35mm) increments using a minimum number of pieces.  Look at the "downloads" for a table of the optimized spacer combinations. 

All extensions and mounts are made from high strength 6061 aluminum alloy and black anodized.  Anti-reflection threading and internal baffles on the largest extension tube help minimize internal reflections.  All internal surfaces are painted and baked with a non-reflecting ultra-flat black paint. 

  • 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.
QTY:  
Price as Configured: $195.00

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Optec AP and DSI Spacer Extension Combinations Download
Optec AP and DSI Spacer Extension Combinations
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