Which designation pertains to maintenance on the MK-45 mod 1 and 2 systems?

The designation that pertains to maintenance on the MK-45 mod 1 and 2 systems is GM-0879. This classification is specifically associated with the technical training required for personnel who will be working with these particular weapon systems. The MK-45 is a naval gun system used by the U.S. Navy, and understanding the right maintenance protocols is crucial for ensuring the system's operational readiness and longevity.

The other designations, while they may pertain to different systems or components within the broader field of Gunner's Mate training, do not specifically relate to the maintenance of MK-45 mod 1 and 2 systems. Each designation is tailored to a specific skill set and area of expertise, which emphasizes the importance of precise training focused on particular systems to ensure efficiency and effectiveness in maintenance tasks.