It is 5-Position 1.25" Filter Wheel For Telecope. and high-quality telescope filter wheel allows you to quickly and easily change. The robustly constructed filter wheel is supplied with a 1.25" eyepiece adaptor, 1.25" focuser nosepiece, T-2 camera adaptor and locking ring. It is ideally suitable for visual observations with 1.25" eyepieces. and with the included T2 adapter it is also perfectly suitable for astrophotography with single lens reflex cameras and CCD cameras.The included T2 adapter comes with a locking ring, whereby high-precision distance regulation becomes possible.Its very sturdy aluminum housing makes it also suitable for heavy cameras. The filters can be changed very quickly at any time, even with the camera mounted or with the eyepiece inserted.The very short design also permits the use of devices with short back focus such as Newton or Dobson telescopes.The filter wheel can be attached to your focuser either by the supplied 1.25" nosepiece adaptor or via a T-thread.