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Kokusai Kohki 3" Mirror Diagonal for Refractors & Large SCTs

5.0 (1 Reviews) Read Reviews Write Review
Brand Kokusai Kohki
Part Number 390TFD

Product Info

Manufacturer Description

To help make the transition to a 3" focuser easier, and for use with their 3" 80mm Masuyama eyepiece, Kokusai Kohki of Japan has also developed a low cost 3 inch star diagonal mirror system that includes the 3" adapter sleeve for easy attachment to your (larger) SCT tube's (larger) visual back. Just screw the 3 inch sleeve on to your Celestron (11" or larger) or Meade (10" or larger) SCT telescope, slide in the star diagonal, then the Masuyama 80mm. and tighten all the lock screws, and you will have instant access to a whole new universe with your long focal length telescope.

As a convenience, also included is a 3 inch to 2 inch eyepiece adapter with this set. To avoid marring or scratching, the sleeves use a wrap around band to lock your eyepiece or accessory into position. Diagonal is made in China.


5.0 (Based on 1 Reviews) 100% of reviewers recommended this product.
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    1. Guest

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      User Notes:
      Review by Guest
      Jun 12, 2019

      5.0 This 3-inch diagonal is very




      This 3-inch diagonal is very well made. I have not used the Cass adapter as i purchased it only for my refractor and there it does just as intended and very well. Nice product and would recommend.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

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