Super Ear (อุปกรณ์ ดักฟัง เพิ่มเสียงได้ถึง 50 db) 

What binoculars did for vision, this product does for listening. Produces an adjustable 50 decibel gain on sounds picked up from its multi-element high sensitivity microphone. With only a single AAA battery, this lightweight device produces nice results. Use to amplify bird sounds (can be clipped to binoculars), frogs at night, or use during a lecture to get all the details. Comes with high quality stereo headphones, AAA battery, instructions and suggestions for use. Begin hearing things you have never heard before.