The Four Block Shirt is one of the many collectibles that you can find hidden throughout the pizzaplex in Five Nights at Freddy’s: Security Breach. This shirt is hidden within Rockstar Row but cannot be retrieved until you have progressed far enough into the game. Here is where you can find the Four Block Shirt in FNAF: Security Breach.
Before you can get your hands on this collectible, you will first need to complete the section of the game where you dodge the Endoskeletons. After this part of the game, you will come across Vanessa talking to Freddy in the upgrade chamber. Head inside and finish the upgrade for Freddy. Once the upgrade is done, you will be allowed to leave this room through one of the service elevators.
The only elevator you will be able to enter will be Roxy’s elevator. Head through the door and take her elevator up to Rockstar Row. You will be in the room behind Roxy’s greenroom. Exit the elevator and look to the left to find a present next to the door leading into Roxy’s room. This present contains the Four Block Shirt.