From the 2011 series Falling Skies, this is the screen used “Scout Whistle” usually used to alert the Espheni "Nazi Youth" leaders of subversive activity, children wear their Scout Whistle around the neck for easy access. Season 4, Episode 4, Tom Mason (Noah Wyle) discovers during his attempt to rescue Matt Mason (Maxim Knight) from the Espheni re-education camp seemingly taken from the pages of a "Nazi Youth" handbook. In Season 4, Episode 9, the 2nd Mass learns that the Scout Whistle also summons Espheni Beamer Airship strikes, when Matt's now-brainwashed friend Mira (Desiree Ross) blows on her Scout Whistle to rat out the 2nd Mass and Cochise (Doug Jones) and signal a Beamer attack on them at a Volm supply depot. Cochise tunes its ultrasonic frequency to hone in on the amplitude used for Espheni Beamers (Season 4, Episode 9). Cochise blows the whistle while the 2nd Mass members watch a startling revelation: their captured, buried Beamer rises from under the massive pile of rubble and hovers above them. The Scout Whistle without the necklace is approx. 3” long and includes a built-in crystal, light, battery, and black necklace.