Which episode of "Naruto" has Naruto and Kyuubi perfectly integrated?

The fusion of Naruto and Nine-Tails is episode 549.

Uzumaki Naruto, the male protagonist in the Japanese comic "Naruto" and its derivative works. A ninja from the Hidden Leaf Village of the Land of Fire, the son of the fourth generation Hokage Namikaze Minato and Uzumaki Kushina, and the chakra reincarnation of Asura, the second son of the Six Paths Sage. When he was born, his parents sacrificed their lives to protect the village and sealed the tailed beast "Nine Tails" inside Naruto.

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Before becoming a genin, Naruto's clothes were mostly T-shirts, in white, navy green and black, with the Konoha logo painted on the chest, and shorts. Wear dark green windshield glasses. After becoming a member of Team 7, Naruto usually wears an orange jacket suit with blue shoulder pads and a white collar: the Uzumaki Clan's mark is sewn on the back and left arm of the clothes, and a kunai bag is tied to his right leg. , wearing blue ninja shoes and the Konoha forehead protector given to him by Iruka.

In the second part, Naruto changed into a black shoulder pad, collar, and sleeves, while the lower part was an orange sportswear, with a gray mesh tights as the base, shoes and forehead protector. Also correspondingly changed to black. When not on missions, he would change into a white or navy green T-shirt with the Konoha logo on it as his daily clothes, and beige shorts.