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ZWO Filter Masks

ZWO Filter Masks

by ZWO
SKU ZWO-EFW-7-MASKS
Save up to 10% Save 10%
CA$21.00
CA$17.00 - CA$21.00
CA$21.00
CA$19.00
CA$15.00 - CA$19.00
CA$19.00
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  • Securely Mounts Unmounted Filters
  • Sets for ZWO 7x36mm, 8x1.25", 2" and Mini EFWs
  • Includes M2 Mounting Screws
  • Prevents Internal Light Leaks
Size
1 in stock
Qualifies for FREE Shipping in Canada on orders over $500.
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • ZWO Filter Masks for EFW Filter Wheels

    This ZWO Filter Mask set provides the hardware for securely installing unmounted filters in a ZWO electronic filter wheel. Each set includes 10 masks and a pack of M2 x 4 screws to hold the filters firmly in the carousel. Choose the set that matches your wheel: EFW-7 masks for the 7x36mm wheels, EFW-8 masks for the 8x1.25" wheels and the 2025 5x1.25" wheel, EFW-2 masks for the 2" wheels, and EFW-5 masks for the previous EFW Mini.

    Installation in 3 Steps

    Replacing or installing filters with these masks is a straightforward process. You only need to remove the filter wheel's back cover, place your filters into their respective slots, and then use the included masks and M2 screws to lock them into position. This design ensures the filters remain perfectly seated and centered in the light path during rotation.

    Which Mask Set Fits Your Filter Wheel

    EFW-7 masks fit the ZWO EFW-7x36, EFW-7x36-II and 2025 EFW-7x36-25. EFW-8 masks fit the EFW-8x1.25 and the 2025 EFW-5x1.25-25 and EFW-8x1.25-25. EFW-2 masks fit the EFW-7x2 and EFW-5x2 and the 2025 EFW-7x2-25 and EFW-5x2-25. EFW-5 masks fit the previous EFW Mini only. A spare set is handy for replacing lost parts or for quick filter changes in the field.

  • What is the purpose of the ZWO Filter Masks?

    The primary purpose of these masks is to securely hold unmounted filters inside a ZWO electronic filter wheel. They press the filter against the carousel, preventing it from shifting or tilting, and block stray light from leaking around the edges of the filter, which is critical for maintaining high-contrast images.

    Are these masks compatible with the ZWO 5-position filter wheels?

    Yes, with the matching set. EFW-8 masks fit the 2025 EFW-5x1.25-25, EFW-2 masks fit the EFW-5x2 and EFW-5x2-25, and EFW-5 masks fit the previous EFW Mini. The EFW-7 masks are for the 7x36mm wheels only.

    How many filters can I install with one ZWO Filter Mask set?

    Each set includes 10 filter masks, enough for a full carousel of up to eight filters with spares left over, plus one pack of M2 x 4 screws.

    I lost the screws for my ZWO EFW. Does this kit include them?

    Yes, each kit includes a pack of M2 x 4 Phillips flat head screws for attaching the masks to the filter wheel carousel.

    When switching from LRGB to narrowband filters in my ZWO EFW, do I need new masks?

    You do not need new masks if your original ones are in good condition. However, having this spare set is highly recommended. It allows you to pre-mount your narrowband filters on the spare masks, making the physical swap much faster and reducing the risk of dropping a tiny screw in the dark while working on your imaging rig.

    Will these masks work with filters from brands other than ZWO in my ZWO EFW?

    Yes, as long as the filters are unmounted filters of the size your wheel takes, these masks will provide a secure fit regardless of the filter manufacturer. They are designed to hold the filter by its edge, accommodating minor thickness variations between brands.

  • SKU Number ZWO-EFW-7-MASKS / ZWO-EFW-8-MASKS / ZWO-EFW-5-MASKS / ZWO-EFW-2-MASKS
    MPN ZWO EFW-7-MASKS / EFW-8-MASKS / EFW-5-MASKS / EFW-2-MASKS
    Product Type Filter Wheel Adapter
    Compatibility EFW-7: 7x36mm EFWs; EFW-8: 8x1.25" and 2025 5x1.25" EFWs; EFW-2: 7x2" and 5x2" EFWs; EFW-5: EFW Mini
    Warranty ZWO - 2 Years

    • ZWO EFW Filter Masks ×10 (set for your wheel)

      × 1

    • M2 x 4 Phillips Flat Head Screws (1 pack)

      × 1

  • ZWO 2-Year Limited Warranty