Quentin wants to give Rowena a pearl necklace that he has in his safe deposit box at Security Bank. The bank is closed for a holiday. Quentin gives Rowena a key to the box and tells her to go to the bank after the holiday and take the necklace. Rowena does this. The next day, Quentin dies unexpectedly. His heirs want the necklace. What type of gift was this? Can Rowena keep the necklace?