Cardas XLR Caps (XLR C SS) fit over unused XLR connectors to eliminate EMI and RF noise absorption. Sold per each.
Please specify if you want the cap to be male or female gender. Use female to cover output. And male to cover an input.
They are non shorting and completely cover the XLR's opening with a solid shield of nickel and brass to prevent EMI and RFI from entering the chassis