William Optics 1.25" Binoviewer with Eyepieces

  • Barrel Size: 1.25-inch.
  • Optical Path: 100 mm (4 inches).
  • Clear Aperture: 20.2 mm.
  • 20 mm Eyepieces and 1.6x Barlow Nosepiece are Included for Better Focusing!


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  • Regular price $268.00

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William Optics 1.25" Binoviewer with Eyepieces


The William Optics 1.25-inch Binoviewer gives you quality and affordability, the best of both worlds! Enjoy the benefits of a BaK-4 quality binoviewer in your refractor, Newtonian or SCT scope!

The WO Binoviewers offer exceptional quality and attention to detail. These telescope binocular viewers are standard with an anodized aluminum finish to compliment any telescope and the anti-marring eyepiece-compression-ring system guarantees stability and security. Large chromed thumbscrews hold the William Optics Binoviewer to your focuser and the system works with a 1.25-inch or 2-inch star diagonal for added viewing comfort. Its 4-inch optical path means you'll have less trouble getting these binoviewers to come to focus with your telescope and the high-quality multi-coatings mean brighter, more contrast-enhanced views! William Optics tests their binoviewers before they leave the manufacturer for collimation and offers a two-year warranty against product defects. Please keep in mind that damage or loss of collimation from dropping or rough handling of binoviewers is not covered under warranty.

Observe dimensional views of the Moon, planets, star clusters, nebulae, comets and more!

William Optics 1.25-Inch Binoviewer Features:

  • Anodized aluminum finish.
  • Large chromed thumbscrews.
  • Anti-marring brass compression rings for your eyepieces.
  • Fully Multi-Coated.
  • Clear Aperture: 20.2 mm.
  • Eyepieces are helical focusing and held in place by compression rings
  • Dimensions: 120 mm x 112 mm x 42 mm
  • Optical Path: 100 mm (4-inch)
  • Weight: approx. 520 g (without eyepieces)
  • Manufacturer's Two year William Optics warranty.

Image Note: The Gallery Image with an attached telescope is for use purposes only. The blue telescope is not included. 

OPT Product Number: WO-E-BINO-P 


Barrel Size1.25"
Free ShippingYes
Interpupillary Distance Range53mm to 75mm
Warranty2 Year Warranty


  • 1.25-inch Binoviewer with anti-marring compression rings.
  • Two wide-angle (66-degree) 20 mm eyepieces.
  • Barlow nosepiece (1.6x).
  • Exclusive gift box.


Customer Reviews
5.0 Based on 8 Reviews
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Filter Reviews:
John B.
Japan Japan

So happy that I purchased the Binoviewer As somebody who is new to this hobby I was undecided as to which eyepieces to buy and I feel like this is a great place to start. The fact the the WO bino viewers come with eyepieces and the amazing price makes this a great first purchase. Also the service from OPT was excellent.

Russell M.
United States
William Optics Binoviewer - a Good Choice

This is a great way to get started in binoviewing. These work fine with my Celestron-11 SCT. When properly connected the magnification is around 150X with the supplied 20mm eyepieces. So not wide field, but great for smaller DSOs like globulars as well as for the Moon and planets. This is a quality product. The only small negative is the included 1.6X OCS (optical correction system) that threads into the binoviewer nosepiece is slightly smaller in diameter than 1-1/4 inch (1.22 inches). Thus the supplied cap for the nosepiece falls off when the OCS is attached. Other than that litlle problem everything has met or exceeded my expectations. I highly recommend this binoviewer.

Steven W.
United States
Excellent low cost binoviewers

I researched several different binoviewers before settling on the inexpensive pair from Williams Optics. They were well packaged and look to be well made. I had no issues whatsoever using them with my C11 SCT. Views of the moon, Jupiter, Saturn, M42 and M13 were all fantastic. Can’t wait to try them with some higher quality eyepieces.

Jean-Pierre B.
William Optics Bino

First I received my Bino with scratches. I called them and they send me a new unit at the moment they have the proof by the carrier that I sent back the defect unit. I received it three days later and I am in Canada!

Better than Advertised

I ordered these after scouring the net for info on binoviewers......their pro and cons......and decided that at this price point, why not. They arrived on time enclosed in an attractive box that had cut-outs for the two Swan eyepieces and the Barlow. First light was tonight with moderate seeing, but WOW did they perform. I was so excited to try them that I did not give them time to adjust to the night air, but it did not seem to matter, they were crystal clear right out of the box. No collimating problems, no failure to merge, no problems tightening the eyepieces, nothing but the rings of Saturn filling both my eyes in 3D!! I could see its rings and the famous Cassini division, with no false color. In the background were stars that were sharp to the edge of the nearly 70 degree FOV,. I could go on, but I think I will go out again and have another look at them through my LX 90. If you are a newbie, or a seasoned amateur who would like to take a space walk in 3D and don't want to break the bank, buy these nocs. Thanks Vinnie and the rest of the crew over there at OPT for offering such a great deal.

follow up

this binoviewer is aboslutely fantastic. in the 18 months ive had this unit i have pushed it to the limits. in 18 months i have completed 5 astronomical league clubs. viewed a few mag 13 galaxy and viewed all carbon stars, seen all 6 stars of the trapizium and quite honestly viewing anything with both eyes is a real treat everyone should try. if you have the money and desire to stop squinting with one eye and see with both eyes wide open who knows you might just find that your jaw is wide open in awwe. my suggestion is get a set and enjoy in the view. happy stargazing Greg