It is only 2 sessions, of 6 hours each aprox. 4 case interviews, plus a presentation, group dynamic, 2 exams (Math and Logic) and one written excercise. It starts around 8 am, and its done by 2-3 pm. No breaks. People there are extremely nice, and will provide you with coffee if you want. Important to remark that 2 of the case studies are "Structured", meaning that they give you a booklet of information, that you got to read for 5 minutes (10 slides), and then the interviewer walks in the room and starts the interview. The point here is to distinguish what is important and what its not towards answering the question. The two other cases are more market sizing, where no information is given. Nevertheless, that doesn't make it any easier. They will try to put pressure on you, and see how you react.