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Explore Scientific  |  SKU: EPWP6840–01

Explore Scientific 68° Series 2" 40mm Waterproof Eyepiece

$519.99 $623.99

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Explore Scientific 68° Series 2" 40mm Waterproof Eyepiece



  • 40mm Focal Length
  • 68° Field of View
  • 2" Diameter Barrel
  • Fully Multi-coated Optics
  • Argon-Filled, Water and Fogproof
  • Slip-Resistant Textured Surface
  • Fold-Down Eyecup


Elevate Your Stargazing Experience to New Heights

The Explore Scientific 68° Series 2" 40mm Waterproof Eyepiece is a jewel in the crown of astronomy enthusiasts who demand both expansive celestial views and intricate detail. Designed with the latest in optical technology, this eyepiece captures the universe in its vast, awe-inspiring beauty, making it the ideal companion for deep-sky exploration.

  • Luxurious 40mm Focal Length: Offers wide-angle views that envelop you in the stars, perfect for sweeping across the Milky Way or delving into nebulae and galaxy clusters.
  • Immersive 68° Field of View: Creates a spectacularly immersive observation experience, bringing the cosmos to life before your eyes with stunning clarity and depth.
  • Optimized Optical Excellence: Featuring advanced computer design, low dispersion glass, and durable multilayer deposition coatings for unmatched contrast, resolution, and a superior flat field across the entire view.
  • User-Centric Comfort and Reliability: Long eye relief and a fold-down silicone eyecup ensure comfortable viewing, even during lengthy stargazing sessions. The argon-filled, waterproof, and fogproof design protects against the elements, guaranteeing the eyepiece's longevity.
  • Enhanced Durability and Ease of Use: The slip-resistant textured surface ensures a secure grip, and parfocal capabilities mean less time refocusing when changing eyepieces, enhancing your observational efficiency.

A Masterpiece of Astronomical Engineering

This eyepiece isn't just about viewing the stars; it's about experiencing them. Its wide field of view allows for full-immersion into the night sky, encouraging the use of averted vision to uncover faint celestial details previously unseen. The parfocal design ensures seamless transitions between observations, keeping your focus squarely on the heavens.

Superior Protection for Pristine Observations

Thanks to its argon-purged construction, the 68° Series 40mm Eyepiece remains protected against internal fogging and contaminants, such as fungus, ensuring that your view remains crystal clear. Argon’s larger atomic size and superior inertness enhance the seal's integrity and the optics' lifespan, providing a stable viewing environment through temperature changes.

Maintenance Made Effortless

Our commitment to excellence extends to the ease of maintenance. Tested to perfection, this waterproof eyepiece ensures easy cleaning without the risk of damaging the internal elements, maintaining its pristine condition for years of exploration.

Your Portal to the Universe Awaits

With the Explore Scientific 68° Series 40mm Eyepiece, embark on an unparalleled journey through the cosmos. Discover the night sky's hidden wonders with an eyepiece designed for the ultimate in astronomical observation.

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Explore Scientific 68° Series 2" 40mm Waterproof Eyepiece | EPWP6840–01 | 812257010493

Explore Scientific 68° Series 2" 40mm Waterproof Eyepiece

$519.99 $623.99





Focal Length

40 mm

Focal Ratio


Field of View



Enhanced multi-layer deposition (EMD) coatings

Argon-purged, water and fog proof

31mm eye relief

45.5mm field stop diameter

Barrel Size



114.2mm length

80.3mm width


998 g | 35.2 oz
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