ZWO Five Position Electronic Filter Wheel - 1.25" and 31 mm

  • Weighs only 300 g and is Smaller Than Your Hand!
  • Amplify Your ZWO Camera's Potential!
  • Filter Positions: Five.
  • Filter Position Sizes: 1.25-inch/31 mm.
  • Power Consumption: 150 mA at 5V.
  • Sale
  • Regular price $199.00

More on the Way* We do not currently have this in stock, but is a common item we carry. More are likely on the way as the manufacturer allows.
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ZWO Five Position Electronic Filter Wheel - 1.25" and 31 mm

The ZWO Five Position Electronic Filter Wheel - 1.25" and 31 mm is a compact and valuable choice for use with your ZWO cameras. Machined from a single block of aircraft-grade aluminum and weighing less than a pound, the ZWO EFW is a perfect accessory for your astrophotography cameras!

The ZWO Five Position Electronic Filter Wheel Features

Optimized Design

Each filter wheel readily accepts 1.25-inch or 31 mm filters. Switch effortlessly between the filters, with its counterclockwise and clockwise turning feature. This filter wheel is perfect for use in conjunction with the ZWO RGBL filter set in conjunction with the ASI1600!

Free of Vignetting

A 10 mm gap between the sensor and filter means you won’t experience any vignetting when in conjunction with ZWO cameras!

Versatile Power

The maximum power consumption of this device is about 150 mAmps at 5V! You can use the single USB cord to power the ZWO Filterwheel Mini from the USB hub of one of ZWO's cooled cameras while using it!

OPT Product Number: ZWO-EFWMINI


Filter Positions5
Filter Size1.25"/31mm
Free ShippingYes
Power TypeUSB (Digital Use)


  1. EFW Mini Body
  2. 1.25-inch Cover
  3. T2 Nosepiece
  4. 1.25-inch Holder (with cover and 2 screws)
  5. T2-T2 Adapter (male)
  6. A Bag of Filter Masks
  7. USB 2.0, 2 meter length Cable
  8. Phillips Screwdriver
  9. A Bag of M2 Screws

Customer Reviews
4.8 Based on 9 Reviews
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Filter Reviews:
Jerry C.
United States United States
ZWO Five Position Electronic Filter Wheel-1.25”

Easy installation, takes up very little room in the optical train, very user friendly and solid construction. Works great for me and my Explore Scientific 127 mm APO refractor. Highly recommend.

Michael M.
United States United States
Great filter wheel

I like the filter wheel. I have it connected to my ASI 183mm pro usb hub on the back of the camera and when you connect the camera to the computer it will also connect the filter wheel. I can confirm that you can screw in 1.25" Astronomik filters 6nm narrow band just fine. That's the filters I use. I had trouble getting the clamp ring attachment off of the camera side of the wheel to the point that I thought it was permanent. Eventually it came unscrewed with effort, so if it seems tight keep trying. Maybe I was a little light because I didn't wasn't to break it.

D. Bishop
Mini is great for LRGB

I bought this product with the ASI 290. It worked great. I loaded 31 mm filters and the overlapping scheme to install the filters with the retainers did work fine. You will need some patience, good vision, and a steady hand, but it is fine. The drivers worked fine, and with multiple capture SW tools, the selection of the correct filter worked just fine. I was pleased with the rotation to just the right spot, and did not have any problems with imaging. 1) After doing the math for all of my imaging needs, I found that 25mm filters will suffice for both the ASI 290 and the ASI 1600. 2) I had buyer's remorse months later, as I ended up getting an 8 position EFW for DSOs. I will use the mini for LRGB planets, and the 8 position for LRGB, Ha, OIII, and SII. If you only want one EFW get the 7 or 8. OPT was great to work with when ordering.

United States
WO Five Position Electronic Filter Wheel

Works as advertised.

Andrew M.
United States
Works as advertised! Great addition

Works as advertised! Great addition to my new ZWO ASI183MM Pro.

too quiet

This is a very well made filter wheel. And it works really well. At first I thought I wasn't doing its job because I expected some whirring sound of some sort. But it is absolutely quiet and, most importantly, no vibration whatsoever. It is as smooth as silk. Mounting the filters is a bit of a puzzle because how it is shown in the manual is not how it is mounted in reality. In the manual they have little red tabs that hold the filters in place. In the box you will find a set of rings with 3 screw holes in them and also a bag of tiny screws. In my opinion that actually works better because now the filter is held in place all around instead of just 3 places. One screw needs to hold 2 rings because the rings overlap