((headphones) jack (3.5 mm dia. stereo mini-jack), 8 ohms. 30(W) 103(H) 21 D) mm ( 2 1/2 4 1/6 27/32 in.). DC 3V using two R03 (size AAA) batteries. Power source. 10 mW +10 mW (EIAJ/32 ohms) 65 mW (EIAJ/8 ohms).
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