Translation:Shulchan Aruch/Choshen Mishpat/343

Paragraph 1- If one borrows an item or any other thing for a set time, as soon as the time comes, the borrowed item reverts to the owner’s possession with respect to exempting the borrower from an unavoidable accident, even if the item is still in his home. He would, however, still be liable if the item were stolen or misplaced, as is the law with respect to a paid watchman. If the borrower sent the item during the loan period with the slave or agent of the owner or borrower, the law is discussed in Siman 340.

Paragraph 2- If one is a paid watchman for a set time, once that time has passed his guarding is complete, and even if the item remained in his home, he would only be an unpaid watchman on it.