Designed to provide extra air while egressing helicopter and ground vehicles after being unexpectedly submerged in water. BRAND NEW IN BOX. Great piece of kit for spare dive air, prepare or survival. The SEA MK & SEA LV2 consist of the basic SEA first stage and cylinder assembly. The products differ in second stage configurations and color of first stage components. SEA MK 2.0. SEA piston First Stage w/integral fill port and choice of pin or dial indicator gauge. Low Pressure Hose in 27-inch lengths. Military Black LPO Second Stage Assembly.