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Explore Scientific  |  SKU: EPWP6820–01

Explore Scientific 68° Series 1.25" 20mm Waterproof Eyepiece

$219.99 $263.99

Bonus offer: after adding this item to cart, add 3 other eyepieces + the soft-sided case to get it for Free ($49.99 value)

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Ships from US warehouse in 1-2 business days

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Explore Scientific 68° Series 1.25" 20mm Waterproof Eyepiece



  • 20mm Focal Length
  • 68° Field of View
  • 1.25" Diameter Barrel
  • Fully Multi-coated Optics
  • Argon-Filled, Water and Fogproof
  • Slip-Resistant Textured Surface
  • Fold-Down Eyecup


Dive Into the Cosmos with Enhanced Clarity and Comfort

The Explore Scientific 68° Series 1.25" 20mm Waterproof Eyepiece stands as a beacon of optical excellence, designed for astronomers who demand wide, clear views of the night sky. This eyepiece combines cutting-edge technology with user-centric features to offer an unparalleled observation experience.

  • Wide-Angle 20mm Focal Length: Delivers expansive views of celestial phenomena, from the delicate structures of nebulae to the majestic sweep of star clusters, all through a generous 68° field of view.
  • Optimal Optical Quality: Engineered with low dispersion and high refractive index optical glasses, coated with advanced multilayer deposition coatings, this eyepiece guarantees high contrast, razor-sharp resolution, and an exceptionally flat field.
  • Comfort-Driven Design: Features long eye relief for easy viewing, even for eyeglass wearers. The soft silicone rubber eyecup, which is removable and foldable, ensures maximum comfort during extended stargazing sessions.
  • Rugged and Reliable: Argon-filled and waterproof construction protects the eyepiece from the elements, while the slip-resistant textured surface and fold-down eyecup enhance durability and ease of use.

Advanced Engineering for Detailed Celestial Viewing

Utilizing state-of-the-art computer design, the 68° Series eyepiece offers a fully immersive visual experience, inviting you to explore the universe with averted vision techniques, thus revealing faint details across a vast field-of-view. The parfocal design minimizes adjustments when switching eyepieces, keeping your focus on the stars.

Protection Against the Elements

The argon-purged body ensures internal components remain pristine, outperforming traditional nitrogen-filled eyepieces by providing a larger atomic barrier against seal leakage. This inert gas prevents chemical reactions that could damage the eyepiece, while its slow thermal conductivity protects against rapid temperature changes, ensuring consistent optical performance.

Easy Maintenance, Long-Term Durability

Tested to perfection, each eyepiece is sealed against internal fogging and external contaminants like dust and fungus, making cleaning effortless. The integrity of the optics is maintained over time, promising years of reliable service and breathtaking celestial views.

Unlock the Mysteries of the Night Sky

With the Explore Scientific 68° Series 20mm Eyepiece, every night becomes an opportunity to journey deeper into space, discovering the unseen beauty of the universe. It's not just an eyepiece; it's your portal to the cosmos, designed for those who seek to push the boundaries of their astronomical adventure.

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Explore Scientific 68° Series 1.25" 20mm Waterproof Eyepiece | EPWP6820–01 | 812257010530

Explore Scientific 68° Series 1.25" 20mm Waterproof Eyepiece

$219.99 $263.99





Focal Length

20 mm

Focal Ratio


Field of View



Enhanced multi-layer deposition (EMD) coatings

Argon-purged, water and fog proof

15.3mm eye relief

22.8mm field stop diameter

Barrel Size



69.6mm length

50.3mm width


247 g | 8.7 oz
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