First Hokage's Necklace

Owners
 * Hashirama Senju - Deceased
 * Tsunade - Former
 * Nawaki - Deceased
 * Dan - Deceased
 * Naruto Uzumaki - Current

History
This is a necklace that is currently owned by Naruto Uzumaki. It was first owned by the First Hokage, Hashirama Senju of Konoha. Later, Hashirama gave it to his granddaughter, Tsunade. On the twelfth birthday of her brother, Nawaki, she passed it on to him as a gift. Nawaki promised that he would protect Konoha with the necklace. However, during the Second Great Shinobi War, Nawaki was killed and Tsunade would have to give it to her lover, Dan. But during the war, he was killed as well, and Tsunade went back to owning it. At the beginning of the Tsunade Retrieval arc, Tsunade made a bet with Naruto that if he could master the Rasengan by the end of the week, Tsunade would give him the necklace, would believe that Naruto will become Hokage someday, and would come back to the village and heal Sasuke. Like most of her other bets, Tsunade lost and Naruto got the necklace. This necklace was regarded as having a curse on it and only Tsunade could wear it; since both Nawaki and Dan died after receiving it.During the Jiraiya,Naruto,Tsunades,and Shizune's battle with Orochimaru and Kabuto Naruto was injured almost killing him.It can be assumed that Tsunade wanted to break the pattern of death surronding the necklace. Naruto seems to be an exception to this since he has worn it for most of Part I and Part II and has not died yet. Or, what seems like a curse might just be a coincidence. It is possible that the necklace's curse is that only those who are destined to be hokage can wear it but those who aren't die. Which is why Tsunade and Naruto are able to wear it.

Abilities
It is said that the First Hokage's Hokage-style Sixty-year-old Technique - Kakuan Entering Society with Bliss-bringing Hands responds to this necklace to suppress the Kyūbi's chakra and saved Naruto after entering Four-Tailed Transformation.