Nikon NIKKOR Z 600mm f/4 TC VR S Lens (Z) - Manual (Page 40)

Press the points on either side of the slip-in filter
holder and open the cover.
Insert a 46 mm screw-on filter.
Depending on their shape, some filters cannot be used with the slip-in filter
holder. Use filters that fit the holder.
40
Filters
2.
3.