Survival Egress Air MK (S.E.A. MK) Wednesday August 28th, 2019 admin Emergency Equipment, Modern Warfare 3,240 views Shown one dated Jul, 30, 2007, came from 2nd MSOB. Stock Number Reference: S.E.A. Breathing, MK NSN: 4220-01-482-7389 Assign Date: 2001-03-01 modernemergencymaritimebreathing_device