Microphone for finding objects

Name :
Chihiro Ishizuka
COUNTRY :
Japan / Kanagawa
AGE :
12
YEAR :
2011
PRIZE :
The Asahi Chugakusei Weekly Prize
COMMENTARY :
When my father, mother, and grandmother are getting ready to leave the house, they often cannot find their key or cell phone. If they call into this microphone, a light or sound comes out of the keys or cell phone, and they can be found easily.
Microphone for finding objects