ZWO Filter Drawer and Filter Holder for Nikon Lens
if you only use one filter for your imaging sessions, this type of filter holder is an economical alternative to filter wheels. ZWO offers in its catalog this system consisting of 2 parts: a filter holder with M42 male thread on the camera side / Nikon compatible bayonet and a removable drawer for filters with a 50.8mm flow.
It measures 70mm in external diameter for 269mm in thickness. An M54 male/M42 female ring allows the input or output to be transformed according to your needs.
The drawer is fixed using magnets and a locking screw to ensure perfect security.