Intervox #BRT1209L-03. 12mm diameter x 8.5mm high. 3.6Vdc (1.5 - 5Vdc), 70mA max current. 90 db @ 10 cm. 2048Hz. Two 3.5" leads.
Note: Used in paging, warning signals, metal detectors and alarm clocks. Miniature magnetic transducers require external signal source to produce sound.