An NT-B caste certificate is sufficient for claiming OBC reservation benefits in the national level reservation scheme.

The central government includes Nomadic Tribe (NT) categories like NT-B within the broader OBC (Other Backward Classes) category for reservation purposes.

Since NT-B falls under OBC, you only need a caste certificate that specifies your caste as "NT-B." This certificate should be issued by a competent authority designated by the state government.

The validity of OBC certificates can vary depending on the specific reservation scheme and issuing authority. In general, OBC certificates issued by the central government are valid for a lifetime. State governments might have their own validity periods for OBC certificates.

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