This 1.25" filter wheel lets you use up to 9 different filters and change them within a couple of seconds -your filters are always remain ready to use, whether for photography or visual observing. Use the filter wheel with UHC, OII, CLS and other filters, for example - this will let you quickly and easily find the best filter when visually observing.Open the filter wheel and screw up to 9 different filters into it. These can be RGB and luminance filters for astrophotography or wide-band and narrow-band filters for visual observing. You can also leave the filters mounted in the filter wheel, where they are optimally protected from dust and damage.Imagine you have a camera mounted on your telescope and have to switch between different filters as quickly as possible. This is only possible using a filter wheel. The handy rotary wheel offers you incredibly fast switching between up to 9 different filters. Each filter position is designated by a number, so you know which filter is currently in the beam path.The telescope side of the filter wheel comes supplied with a 1.25" adapter, allowing you to quickly and easily attach it to your focuser. The filter wheel also has a T-2 thread on the telescope side for other adapters. On the accessory side, you will also find a T-2 and M48 thread.The filter wheel interior is absolutely light-tight - allowing you to image without any reflections or stray light.