The type of Hadith in which the chain of narrators remains unbroken and continuous is called:

In the science of Hadith, a Hadith in which the chain of narrators remains unbroken and continuous from the first narrator all the way back to the Prophet Muhammad (PBUH) is called Mutassil (or Musnad). This continuity is a crucial criterion for assessing the authenticity and reliability of a Hadith, ensuring that no links are missing in its transmission.

• A Hasan Hadith is a classification based on the strength of its narrators and chain, being good but not as strong as Sahih.
• A Mutawatir Hadith is one narrated by such a large number of narrators at each stage that it is impossible for them to have conspired to fabricate it; it focuses on the number of narrators, not just continuity.