An OPNAVINST or OPNAV Instruction is a formally documented lawful order that is issued by the Chief of Naval Operations.
These instructions are typically used to establish United States Navy policy, procedures, and requirements.
The instructions are issued in the form of a memorandum on official Department of the Navy letterhead.
For a list of OPNAV Instructions you can refer to the Department of the Navy Issuances website.
For specific examples, see below: This United States Navy article is a stub.