Mainly a styling exercise but also saves a bit of weight into the bargain. Various makes and styles out there Oberon, Harris etc. They don’t tend to list our model of bike but it’s the same as a Ducati 916,851,888,998,996,748 etc as well a few Monsters too.
It’s a 5 bolt cap but only three affix the cap the other two are dummies. The rubber flange will have to be reused to take up the gap around the cap to the tank just like the stock cap. This also (well at least from the caps I have fitted) needs to be cut out to allow the keyless cap to fit flush.
All best described with a pictures I feel.