Board Thread:Naruto Discussions/@comment-43317375-20200727034617/@comment-46279039-20200728063405

Chakra mode is related to the way Kurama was sealed. The eight trigrams seal. You can clearly see the seal visible in all transformations. is a filter that allows Naruto to use Kurama chakra without becoming Kurama. Even when opened, Kurama can still give his chakra in that way.