This unit runs in auto or manual mode. This is a brand new unit with a warranty. Many of our customers have been asking for this EKG machine, it is a small, portable, handheld EKG machine at low cost. This unit can also run in manual mode. This unit is a special North American model, with USA coded patient cable and alligator clips. Included is software and a PC USB Cable so ECG recordings can be uploaded and filed on a computer. Do not confuse this model with lower cost Asian model units. This unit comes complete with cables, battery pack, power supply recording paper, PC USB cable, software and operating manual. Filter: AC 50/60Hz Lead selection: Automatic and Manual Operation mode: Battery or AC Weight: Less than 1 pound Recording system: Thermal-array printing Chart Paper: Low cost roll type