Are the new child's backpack with a security alarm built-in, a fad or the real thing?

I saw this commercial on tv last night. Wife and I wondered if this was just a gimmick supposedly for children’s safety or was it the real deal. A siren that blows and a light that flashes, when a child pulls the rip cord on the backpack. This is suppose to scare the threat away from the child. Question: Is this siren, flashing-light backpack a real safety item for a child, or is it just a gimmick to line someone’s pocketbook with our money?