The file 'BNC Adapter Sleeve For RTL-SDR 3D Printer Model' is (stl) file type, size is 21.7KB.
With the adapter to BNC, the RTL-SDR can be safely adapted to antennas.
In fact, I often use SDRs on the move with different antennas. To protect the rather sensitive SMA socket, BNC helps to protect the connection and also makes changing antennas faster.
The sleeve is between the adapter and the housing and helps to stabilise the adapter.
au-housing-cover-topshort_v0.0.stl | 106.3KB |