It is a presale. You can see the last pending transaction "wise claiming day". They should allow to view the total users invested for each day and how much Ethereum they've collected.
As I can see with the last one, it has collected 57900 ETH.
I wonder if that collection is real or just randomly created to make people believe that the project is well funded and has lots of investors since there is no way we can verify the collection and there is no information, as you stated, of the number of investors.
I remember one project announcing that they had collected million dollars worth of investment on their site but later on cancelling the ICO because no one invested on their crowdfunding.