These translucent so you can see the LED indicator light are flexible covers to help protect the buttons, headphone jack plug and charging socket from getting mud and dirt into the ports.
They will not make your headphones waterproof but will help reduce the chances of rain running down the shells into the none sealed push buttons and ports and keep dirt from your hands getting into the charging port.
If you wish to use wired to your detector there is a removable plug to allow access to plug in your 3.5mm jack lead.
Each kit comes with one cosmetic dummy shell for the non button side and one with for the button side with the +Volume, power and -volume buttons.
To charge headphones slip the shell back and plug in charging lead.
Also included is a spare headphone jack port blanking plug.
Fitting involves removing the two screws that hold the headphone cups to the over the head loop, See images.
Does not include the headphones or any other props for photo demonstration.