Sorry, I was speaking of L screw, that limits the travel of the derailer towards the wheel! I have problems with remembering low and high gear, that's why tend to speak of larger or smaller sprockets.

The cassette is made of single sprockets, but the three or four biggest are connected through spacers with allen key type "bolt" (sorry for my lack of technical english), but technically they are all single sprockets, I know since I dismantled the casssete some time ago to clean it.