A snap in adapter with m8x.75 threads for a 3.5mm panel mount audio jack to tie into the SidTap header of the Ultimate64 motherboard. 3.5mm jacks can be found on ebay or aliexpress. Thread the jack into the adapter and push the entire assembly into the RF hole of the 64c or pixelwizard case. There is a small ridge on the outside barrel of the adapter for a snap in fit that can later be removed if needed. I have not tried a breadbin case for this adapter. Update: I included a modified veion for U64 Elites and other taller Sids. This pushes the jack out of the case another 3mm. I have not tested it, so any input on the modification would be helpful.