"MEASURES FLATNESS OF SURFACES.AUTOMATIC SETTING OF ABSOLULTE ZERO, PRESET FUNCTION OF ANGLES. POWER SUPPLY: 4 AA 1.5 V ALKLINE BATTERIES (34 HOURS), OPTION 4 AA 1.2 V NIMH RECHARGEABLE BATTERIES (20 HOURS), EXTERNAL POWER SUPPL +12..+48 V DC, POWER CONSUMPTION: BATTEREIS 250 MW, EXTERNAL POWER SUPPLY 500..3000MW."