Starizona RASA 8 Filter Drawers for ZWO Cooled Cameras (see list below)The Rasa 8 filter drawers can be pulled in and out using a small knob. This knob is required because the filter slider will be completely flush with your camera, leaving no room to grab the filter drawers. Extra Filter Drawers can be purchased separately.This Filter System will ONLY work with the following cameras on the RASA 8. - ZWO ASI1600MM Pro - ZWO ASI1600MC Pro - ZWO ASI294MC Pro - ZWO ASI294MM Pro - ZWO ASI533MC Pro` - ZWO ASI183MM Pro - ZWO ASI183MC ProSpecifications. - Diameter: 3.10" (78.8mm) - Thickness: 0.76" (19.5mm) - Telescope Side Threads: M42 Female Threads - Camera Side Threads: M42 Female Threads - Filter Size: Standard 2" - Weight: 5 oz. (140g)Using the Filter Slider on the RASA 8The optical window in the RASA 8 will stay in place. The Filter Slider accounts for the extra optical path length of the filter glass.Note the Filter Slider can be installed upside down since the threads are the same on both sides, but it will only work in one orientation. The top can be determined by the Starizona logo being right side up. The drawer itself goes all the way up to the top but does not extend all the way down, allowing the drawer to come out without hitting the RASA retaining ring. If the drawer hits this ring, the Slider is probably upside down.Remove the black 11mm female M42-threaded ring from the front of the ZWO camera. The red male M42 threads on the camera will then go into the female threads on the top of the Filter Slider.