Qty 20 - Noise Canceling RCA Caps / Shielded Shorting Plugs offer EMI and RFI Protection These GOLD PLATED CAPS / COVERS / PLUGS insert into unused RCA inputs on: Stereos, DVD players Cable boxes Boom boxes AV receivers Gold plating insures best performance! Can be used on any AV equipment RCA inputs. Seconds to install or remove Helps block unwanted EMI / RFI interference Also helps to keep dust and dirt from entering system Larger qty's available - just ask!