On this page of our Little Nightmares 2 guide, you will find the exact location and description of all the Hats you can earn in stage 4, Enter the Tower.
Location: Chapter 4, at the post office.
To get to this hat you must go down the shaft located on the left side of the wall. Right next to a pile of letters.
Location: Chapter 4, the store.
To get to this hat you simply need to jump on the ledge located on the left side. You will get there by using the cart. You need to pull it so that it is right up against the shelf.
After climbing onto the ledge, head to the very edge of the ledge on the left. There on the box you will find the hat.