1.25 inch nosepiece with M42 thread
An adapter to allow a camera to be connected to a 1.25" focuser.
Do you need to attach a camera (either a DSLR with a t-ring or a CMOS) to a 1.25" focuser, while also being able to use a 1.25" filter such as a light pollution filter? Then you need this.
On one end of the adapter is a standard 1.25" barrel, like you'd find in a standard eyepiece. The other end of the adapter is an M42 (42x0.75mm) male thread. Your t-ring or ZWO camera will connect straight onto the telescope. The 1.25" filter you can then thread into the end of the 1.25" barrel, as you would with an eyepiece.