SPECTRA PRECISION HV301G GREEN BEAM SELF LEVELING ROTARY LASER LEVEL. I do not know how to operate the item. When powered ON the device runs 5-10 seconds (green lasers come on) BUT then the unit shuts itself OFF.Might need new rechargeable batteries??? I did not try to repair (nor did I even attempt to repair) this electronic device. There is absolutely No Corrosion in the battery chamber (see detailed photos). Includes Everything You See in the Photos. No Other Accessories if Not in Photographs.