Cpl. Tyler Raffaele, an entry team breecher with the Special Reaction Team, Marine Corps Police Department, Security Emergency Services Battalion, performs a scan of his surroundings immediately following a course of fire during a quarterly SRT qualification at Range 300, Nov. 20. The scan is a tactic used to remain aware of your surroundings and break tunnel vision in combat. - Cpl. Tyler Raffaele, an entry team breecher with the Special Reaction Team, Marine Corps Police Department, Security Emergency Services Battalion, performs a scan of his surroundings immediately following a course of fire during a quarterly SRT qualification at Range 300, Nov. 20. The scan is a tactic used to remain aware of your surroundings and break tunnel vision in combat.