It depends on the helmet if you only use the Ksmera on its own, you can attach it to the visor with a clip, which is how I do it on my MTB helmet. If you want to attach it with the housing, it has a fastener on the underside of the housing with a hook and magnet. You can get a wide variety of attachments for this, so it can certainly be attached somehow. 👍🏼

very well, this device comes with probably one of the most options to mount to things then any action cam ive seen, you can use go pro mounts if your current device is a go pro. it comes with a pretty good sticky mount, which I have used to mount to the bonnet of my car for some spirited mountain pass runs.
It has a killer magnetic mount should you choose to mount it to your chest, you can buy clamp mounts for your bike handle bars. I would be very suprised if you could not mount it to your helmet, a mount will be required, you will need to check the site or be createive, but I am near 99% positive you can stick this to anything. That said, even tho go go3 is alot better then the go2, I found the Go2 much easier to use.

Hello
Secure attachment to the motorbike helmet is only possible with an additional quick release/quick release mount (fruugo approx. CHF 35, for example), which serves as an adapter/connector for attaching to the Go Pro mounting gadgets available everywhere. Unfortunately, these brackets are not yet available to order from Digitec...

With the clip you can attach it very easily to a helmet that has a peak. Otherwise also very easy to attach, as the camera is ultra-conductive.