It is not intended for industrial or commercial applications. 2. Technical Data Power supply: External mains adapter: 3 V DC, min. 300 mA (not included) or batteries: 2 Alkaline batteries, 1.5 V Type "AA“ (please do not use storage batteries) Tape speeds: 1.2 cm/s or 2.4 cm/s Frequency range: 250 - 4500 Hz Dimensions : 126 x 68 x 26 mm (W x H x D) Weight: 140 g without batteries Cassette type: Standard microcassette, up to 60 min. 3. Package contents 1 Lervia KH 4111 mini-dictaphone 1 Microcasse