When we’re talking about a headset, we’re talking about the whole set of parts that make the bars turn. It includes 2 Campy spec bearings, a pinch ring for compression, a top cap for dust protection / look and finally a race cup for compression (This part of the headset is almost never neccessary, most forks now come with this part integrated directly).
There are 2 big types of headsets, one of which is almost extinct:
The vast majority of freestyle scooters come with integrated headsets nowadays. They come with sealed bearings and for us, to be considered as a «freestyle» scooter, this is mandatory. They can take more abuse, forgive when riding a bit loose and are compatible with all the aftermarket parts. They have become the standard in the scooter industry. If a scooter does not come with one, we classify it as a youth scooter, even if it is rigid and skatepark ready
External headsets are easy to spot by being, well, external to the deck. You will see 2 black (usually) cups, one at the top, one at the bottom. Those cups are where the bearings are and not all of them are sealed. In fact, in the scooter world, the vast majority will not be sealed as those are used on cheaper scooters.
Since the bearings sit directly in the deck, you just have to put them in. We recommend greasing everything with thick grease to avoid any friction.
Ideally, for taking those cups out and putting them in, you need special tools made for external headset. We highly recommend to go to your local scooter shop or bike shop for that type of installation.