Aegis in Greek means shield or protection and is also the code name for the world's premier integrated air defense system and the sea-based element of the United States Ballistic Missile Defense System. Features S.A.T. (SOG Assisted Technology)This mechanism helps propel the blade open once the operator has initiated the one-handed opening action. Sliding bolt action with piston lock mechanism. Additional safety lock when blade is closed. • 4” closed frame lock • 3” assisted opening black finish • AUS-8 stainless blade with dual thumb studs • Additional safety lock when blade is closed