You can only bring the weapons, Slabs, trinkets, and information you learn between districts in Deathloop. Those are primarily the items Colt is carrying on himself as he attempts to take out the various Visionaries running the island. Many items also need to be brought from one district to another, but they can’t come with him through the tunnels. Instead, he has to use the delivery system.
The delivery system in Deathloop is the only way to bring larger items. You can find a delivery station in every district. However, before you can use these systems, you’re going to need to find the code associated with them. Those codes are hidden in the respective districts, and once you’ve learned that code, you’ll have it for the rest of the game. It cannot be taken away from you.
The trick is finding these codes. From there, you’ll be able to transfer items, such as the crank-wheel. It’s a bulky item that you’ll have to devote your right hand to holding, making it difficult to walk around with. Also, you want to make sure that you do not start the loop over after you’ve transferred an item through the delivery system. You want to make sure you transfer the items between districts during the same day, or you’ll have to do it over again.
While finding the codes for the delivery system can be a little tricky, it’s a worthwhile way to advance your progress in Deathloop and give yourself an edge over the Visionaries and Julianna.