Skip to content
Until May 2nd, 2025, orders under US$800 will not incur any duties or taxes upon delivery. Please note that orders under US$800 crossing the Canada-USA border after this date will be subject to duties. They will be billed by the carrier, and you will be responsible to pay them. Prioritize ordering items that are in stock!
Until May 2nd, 2025, orders under US$800 will not incur any duties or taxes upon delivery. Please note that orders under US$800 crossing the Canada-USA border after this date will be subject to duties. They will be billed by the carrier, and you will be responsible to pay them. Prioritize ordering items that are in stock!

Diagonals

Filters

  • $92.00 USD - $92.00 USD
    $92.00 USD
    $92.00 USD - $92.00 USD
    $92.00 USD

    William Optics 45° Erecting Prism - 1.25"

    WO-D-EP125

    45-degree erecting prism for 1.25" telescope eyepieces Provides correct image orientation for terrestrial and astronomical viewing Des...

    View full details
    $92.00 USD - $92.00 USD
    $92.00 USD
    $92.00 USD - $92.00 USD
    $92.00 USD
  • $96.00 USD - $96.00 USD
    $96.00 USD
    $96.00 USD - $96.00 USD
    $96.00 USD

    William Optics 90° Erect Prism - 1.25"

    WO-D-EP90-125II

    90-degree erecting prism for 1.25" telescope eyepieces Provides correct image orientation for terrestrial and astronomical viewing Des...

    View full details
    $96.00 USD - $96.00 USD
    $96.00 USD
    $96.00 USD - $96.00 USD
    $96.00 USD
  • $110.00 USD - $110.00 USD
    $110.00 USD
    $110.00 USD - $110.00 USD
    $110.00 USD

    William Optics 99% Dielectric Dura Bright Diagonal - 1.25"

    WO-D-125D-C-DB
    1 in stock

    High-quality 1.25" diagonal for refractor and catadioptric telescopes 99% reflectivity dielectric coating for maximum light transmission ...

    View full details
    $110.00 USD - $110.00 USD
    $110.00 USD
    $110.00 USD - $110.00 USD
    $110.00 USD
  • $158.00 USD - $158.00 USD
    $158.00 USD
    $158.00 USD - $158.00 USD
    $158.00 USD

    William Optics 99% Dielectric Dura Bright Diagonal - 2"

    WO-D-DIG2D-C-DB-T
    2 in stock

    High-quality 2" diagonal for refractor and catadioptric telescopes 99% reflectivity dielectric coating for maximum light transmission ...

    View full details
    $158.00 USD - $158.00 USD
    $158.00 USD
    $158.00 USD - $158.00 USD
    $158.00 USD
  • $137.00 USD - $137.00 USD
    $137.00 USD
    $137.00 USD - $137.00 USD
    $137.00 USD

    William Optics RedCat Erecting Prism - 1.25" Silver Version

    WO-D-EP90-125-RC51-SL

    1.25" erecting prism for correct image orientation Silver-finished design specifically for RedCat telescopes Description The W...

    View full details
    $137.00 USD - $137.00 USD
    $137.00 USD
    $137.00 USD - $137.00 USD
    $137.00 USD