In our LEOS-50 #satellite platform there are regularly two star trackers. For this purpose we are using both the ST200 and the ST400 that Berlin Space Technologies GmbH has developed in collaboration with our partners from Hyperion Technologies B.V.
Bonus question: the ST200 is normally much smaller than the ST400 Why are they similarly sized in this application?
Answer: both star trackers are mounted on the backside of the payload interface plate and thus need to pass once through the entire bus section. The baffle will thus have the same length to reach the end of the satellite. In fact there is a second stage baffle mounted on top of the ST200 standard baffle visible in the picture.