The SBIG 8 Position Filter Wheel for STF-8300 Cameras was designed around of the 8300 CCD sensor. Usually, 1.25" filters are not big enough when on imaging systems with focal ratios faster than f/7 because they don't fully cover the sensor cause vignetting in the corners. Especially at shorter focal lengths where this effect is amplified. The SBIG 8 Position Filter Wheel for STF-8300 Cameras addresses this by using 36mm filter. It has a thin design, adding only 20 mm of back focus to your imaging train! Please note that total back focus for STF-8300 with the FW8-8300 is 38 mm.
The telescope side of the filter wheel has a round adapter plate with standard t-threads. This piece can be removed and replaced with 2"x24 SCT thread plate, 2.156"x24 SLT plate or even a Canon or Nikon lens adapter.